^{page 305 note *} Mag. Zool. and Bot. vol. i. 1837Google Scholar; and Catalogue of Worms, 1865.

^{page 305 note †} Annals N. Hist. xv. 1845Google Scholar.

^{page 305 note ‡} Report Brit. Assoc. 1851.

^{page 305 note §} Annales des Soc. Nat. 3^me ser. vi. 1846; and Voyage en Sicilie, vol. ii. par MM. Edwards, de Quatrefages, and Blanchard.

^{page 305 note ∥} Zeitschrift für wiss. Zool. xii. 1863.

^{page 305 note ¶} Annales des Sc. nat. tom. xxi. 1830.

^{page 305 note **} Annales des Sc. nat. 3^me ser xii. 1849.

^{page 305 note ††} Symbolæ Physicæ, 1831.

^{page 305 note ‡‡} Neueste Schrift. der Naturforsch. in Danzig, 1842.

^{page 305 note §§} Beiträge zur Naturg. der Turbellarien, 1851; and Zeitsch. für wiss. Zool. iv. 1853, &c.

^{page 306 note *} Zeitschrift für wiss. Zool. xii. 1863.

^{page 306 note †} Entwurf einer Syst., &c., der Plattwürmer, 1844.

^{page 306 note ‡} Memoires des Sc. des Acad. Roy. de Belgique, tom, xxxii. 1861.

^{page 306 note §} Recherches Anatomiques, &c., dans les Hebrides, 1861.

^{page 306 note ∥} Mem. sulle Storia, &c., vol. ii. Naples, 1825Google Scholar.

^{page 306 note ¶} Leçons sur la Physiol. et l'Anat. Comparée, tom. 5^me, pp. 460–65.

^{page 306 note **} In his “General Outline of the Animal Kingdom,” 3d edit. 1861, Professor Rymer Jones strictly follows this author.

^{page 309 note *} Nemertes carcinophilus, Kölliker.

^{page 309 note †} The comparison of the external tissues of certain remarkable processes, occurring on a new Annelid from the Gulf of Suez, to the Nemertean skin, as described by M. le Dr Léon Vaillant in the “Ann. des Sc. nat.” for 1865, is certainly far fetched and unlikely. The processes referred to are considered buds, but they seem to me to be no more buds or parasites, than the processes on the long tentacles of our British Mæa mirabilis.

^{page 310 note *} Beiträge zur Naturges. der Turbellarien, tab. vi. fig. 4.

^{page 310 note †} Zeitsch. fur wiss. Zool. bd. xvi. 1866, p. 375

^{page 310 note ‡} Van Der Hoeven, apparently from following M. de Quatrefages, makes the same errors—Handbuch der Zoologie, vol. i. p. 212.

^{page 314 note *} Entwurf einer syst. Eintheilung, &c. der Plattwürmer, tab. iii. fig. 51.

^{page 314 note †} Entwurf &c. p. 94, fig. 18 (woodcut).

^{page 314 note ‡} Recherches Anat. and Zool. vol. ii. pl. xviii. fig. 4.

^{page 315 note *} Op. cit. fig. 1, pl. xviii., and fig. 1, pl. xix.

^{page 315 note ‡} Report, Brit. Assoc. 1851.

^{page 315 note ∥} Zeitsch. für wiss. Zool. xii. pp. 69 and 71.

^{page 315 note ¶} Notes of Lectures at the Roy. Coll. Surgeons, Med. Times and Gaz., March 7, 1868.

^{page 315 note †} Op. cit. pl. xxii. fig. 1.

^{page 315 note §} Op. cit. p. 26.

^{page 316 note *} Phil. Trans. Part ii. 1852, p. 627, pl. xxxii. fig. 25.

^{page 317 note *} Op. cit. pl xix. fig. 1.

^{page 318 note *} Op. cit. plate xx. fig. 3.

^{page 319 note *} Catalogue Brit. Museum, p. 285.

^{page 321 note *} Ann. Nat. Hist. xv. 1845.

^{page 322 note *} Op. cit.

^{page 323 note *} Recherches Anat. sur les Annélides, &c. plate v. fig. 6.

^{page 324 note *} Beiträge zur Naturges der Turb. tab. vi. fig. 10, a.

^{page 324 note †} Recherches Anat., &c. p. 79.

^{page 324 note ‡} Beobachtungeu über Anat. und Entwicklung, &c., 1863.

^{page 328 note *} Op. cit. tab. v. fig. 3.

^{page 333 note *} Vide the admirable Researches of Dr Pettigrew, Philos. Trans. part ii. 1867.

^{page 333 note †} Recherches Anat. &c. p. 166.

^{page 334 note *} Op. cit. pl. xiii. fig. 8.

^{page 334 note †} The Nareda superba of Stimpson has likewise two eyes, but has no longitudinal stripes.—Synopsis Mar. Invert. of G. Manan, N. Brunswick, p. 28, fig. 17, 1853.

^{page 336 note *} Op. cit. pl. x. fig. 8.

^{page 336 note †} “Quelquefois, surtout chez le Némerte balmée, on aperçoit même un commencement de la tige du stylet.”—Op. cit. p. 166.

^{page 339 note *} Catalogue of Worms, &c. p. 292.

^{page 339 note †} Mag. Zool. and Bot. vol. i. p. 531, fig. 4.

^{page 339 note ‡} Recherches Anat. sur les Annel. Turb., &c. p. 81, plate v. fig. 6.

^{page 341 note *} Mémoires l'Acad. Roy. &c. pl. iii. fig 6.

^{page 342 note *} Leçons sur la Physiol. et l'Anat. Comp. tome v. p. 464, 1859.

^{page 343 note *} Mag. of Zool. and Bot. vol. i. p. 530, 1837Google Scholar, copied into “Catalogue” Brit. Mus. pp. 285–6 1865.

^{page 343 note †} Report Brit. Assoc. 1851.

^{page 343 note ‡} Op. cit. pl. xi. fig. 64.

^{page 343 note §} Beiträge zur Naturges der Turb. 1851, p. 62, tab. vi. figs. 2–10.

^{page 343 note ∥} Op. cit. tab. vi. fig. 3.

^{page 344 note *} Recherches Anat. sur les Annélides, Turb. &c. 1861, p. 81, pl. v. fig. 6.

^{page 344 note †} Beobach. über Anat. und Entwicklung. wirb. Thiere, &c. 1863, p. 23, tab. iv. fig. 10–12.

^{page 345 note *} Mém. de l'Acad. Roy. des Sc. de Belgique, tom, xxxii. pl. iii. fig. 7.

^{page 345 note †} Op. cit. p. 44. Unfortunately this author has not lettered his plates, so that I have often been at a loss as to his interpretation of structures of which no mention is made in the text.

^{page 345 note ‡} Zeitsch. für wiss. Zool. Bd. xii. p. 72, taf. v. fig. 4.

^{page 347 note *} Monograph of the British Spongiadæ, Ray Society, vol. i. p. 5, et seq.

^{page 347 note †} Mémorie sulla, &c. vol. ii. 1835Google Scholar.

^{page 347 note ‡} Op. cit. pl. xix. fig. 1, m. Op. cit. pl. ii. a fig. 5.^*

^{page 348 note *} Op. cit. p. 70.

^{page 348 note ‡} Beobachtungen über, &c. pl. v. fig. 10. ph.

^{page 348 note †} Mém. l'Acad. Belgique, pl. iv. fig. 13.

^{page 350 note *} Op. Cit. p. 152.

^{page 350 note ‡} Mag. Zool. and Bot. vol. i. p. 532.

^{page 350 note †} Op. cit. e.g. pl. xviii. fig. 1, and pl. xix. fig. 1

^{page 350 note §} Report Brit. Assoc. 1851, pp. 244–5.

^{page 351 note *} Philos. Transact. 1858.

^{page 351 note †} Op. cit. p. 64.

^{page 351 note ‡} Op. cit. taf. i. fig. 35.

^{page 353 note *} Jour. Micros. Sc. 1865.

^{page 353 note †} Jour. Micros. Sc. vol. v. N. S., pl. viii. fig. 5, k.

^{page 355 note*} This species has since been found in the Channel Islands. It is the Cerebratulus spectabilis of M. de Quatrefages.

^{page 355 note †} Op. cit. pl. xviii. fig. 1. and pl. xix. fig. 1; also in his recent Hist Nat. des Annelés, pl. iv. figs. 2 and 3.

^{page 356 note *} Op. cit. pl. xxi. fig. 3. Polia sanguirubra.

^{page 356 note ‡} Zeitsch. für wiss. Zool. pp. 85–87, taf. v. & vi.

^{page 356 note †} Op. cit. p. 64, pl. vi. fig. 2.

^{page 356 note §} Beobach. über, &c., taf. v. fig. 10.

^{page 358 note *} Op. cit. e.g. pl. xv. fig. 14; pl. xviii. fig. 1; pl. xix. fig. 1; and the whole of pl. xxiv.

^{page 358 note †} Beiträge zur Naturges. Turb., 1851.

^{page 358 note ‡} Zeitsch. für wiss. Zool. iv. 1852Google Scholar.

^{page 359 note *} Beobachtungen, &c. pl. v. figs. 10 and 12.

^{page 359 note †} The arrangement of the nervous system in the curious foreign Turbellarian, described under the names of Bipalium, Stimpson and Grube, Sphyrocephalus, Schmarda, and Dunlopea, Perceval Wright, presents a considerable variation from the foregoing, just as the external form of the head and the digestive system do. Schmarda represents the cephalic ganglia as quite separated from each other, except by connecting cords, and the great nerve-trunks placed close together in the median line, with an intervening ganglion at regular distances.

^{page 359 note ‡} Beiträge zur Kenntniss Wirb. Thiere, p. 72.

^{page 360 note *} Beobach. über Rad. und Würmer in Nizza, Zürich, 1858.

^{page 361 note *} I have a strong suspicion that this is the same species as the Borlasia camillea of M. de Quatrefages, which he places next B. angliœ, an association, if I am correct, founded on erroneous principles.

^{page 362 note *} Zeitsch. für wiss. Zool. xii. 1863, pp. 81 and 82.

^{page 362 note †} Beobach. über, &c. pl. v. fig. 12.

^{page 363 note *} Recherches, &c. Mém. 1'Acad. Belg. t. xxxii. pl. iii. fig. 11.

^{page 365 note *} Op. cit. pl. xxi. fig. 4, and still more plainly in pl. xxii. fig. 2.

^{page 365 note †} Op. cit. pl. xix. fig. 6.

^{page 365 note ‡} Philos. Transact. 1858, p. 131.

^{page 367 note *} It is curious that in the young of Planaria also four eyes should be a common arrangement: indeed, they are present in some species before the embryo leaves the egg.

^{page 369 note *} Op. cit. pl. iii. fig. 28.

^{page 370 note *} Op. cit. p. 65, tab. v. figs. 7, 8, and 9.

^{page 370 note †} Op. cit. pp. 89 and 90, taf. vi. figs. 2 and 3.

^{page 371 note *} Beobachtungen über Anat., &c, p. 23.

^{page 371 note †} Ann. Nat. Hist., 4th ser. vol. i. 1868, p. 229Google Scholar; and Archiv für Naturges. 1868.

^{page 372 note *} Report Brit. Assoc. 1851, p. 171.

^{page 372 note †} Op. cit. p. 243.

^{page 373 note *} Gordius tænia, Dalyell, Pow. Creat. vol. ii.

^{page 377 note *} Memorie sulla storia, &c., vol. ii. 1825Google Scholar.

^{page 377 note †} Neueste Schriften der Naturforschenden, &c. p. 95, 1842.

^{page 378 note *} Op. cit. pl. xxiii, fig. 1.

^{page 378 note †} Op. cit. pp. 66–68.

^{page 378 note ‡} Müller's Archiv für Anat. 1864, p. 595.

^{page 379 note *} Op cit. pp. 68 and 69.

^{page 379 note †} Beiträge zur Kenntniss, &c. p. 70.

^{page 380 note *} Neue Turbel. Rotat. und Anneliden, vol. i. pt. 1, 1859Google Scholar.

^{page 381 note *} Op. cit. taf. v. fig. 16.

^{page 381 note *} See p. 375.

^{page 383 note *} Observat. Anat. de Vermibus quibusdam Maritimis, Berolini, 1852Google Scholar.

^{page 383 note †} Ann. Nat. Hist., 1859.

^{page 383 note ‡} Dr Baird, in describing Serpentarin Berryi, n. sp., also alludes to the very common practice of ejecting the proboscis (not the alimentary canal) after immersion in spirit. It is a habit common to all the Nemerteans.—.Proceed. Zool. Soc. Feb. 12, 1866.

^{page 383 note §} Pow. Creat. vol. ii.

^{page 383 note ∥} Op. cit. p. 10.

^{page 384 note *} Op. cit. p. 17.

^{page 384 note †} Op. cit. taf. vii. fig. 5.

^{page 385 note *} Magaz. Zool. and Botany, vol. i. p. 534, pl. xviii. fig. 1 * *Google Scholar.

^{page 386 note *} Beiträge zur Kenntniss, &c.

^{page 386 note †} Zeitsch. f. wiss. Zool. bd. i. pp. 1 and 2, taf. i. fig 4.

^{page 386 note ‡} Beiträge zur Naturges. Turb., &c.

^{page 386 note §} Op. cit.

^{page 386 note ∥} Op. cit. p. 70.

^{page 386 note ¶} Quart. Jour. Micros. Sc. &c., April 1867.

^{page 388 note *} Since the foregoing was communicated to the Society, I find that Prof. Keferstein, in a recent paper, gives a drawing of a parasite very similar to the above, but he does not say more about it than simply mention, under the explanation of the plate, that it is an enigmatical body from the stomach of a Leptoplana tremellaris. Beiträge zur Anat. u Entwicklungeschichte Seeplanarien von St. Malo (Der K. Gesellsch. der Wissensch. vorgel. am 4. Januar 1868), p. 37, taf. ii. fig. 8. It is probable that the same parasite, as in the case of the Gregarinæ, may have a wide distribution.

^{page 388 note †} Annals Nat. Hist. xv. 1845Google Scholar.

^{page 389 note *} Rept. Brit. Assoc. 1851.

^{page 389 note †} Powers of the Creator, vol. ii. p. 73.

^{page 389 note ‡} Zeitsch. f. wiss. Zool. xii. p. 70.

^{page 391 note *} Proced. Linn. Soc., June 1868.

^{page 392 note *} Neueste Schriften, &c.

^{page 392 note †} Beiträge zur Kenntniss wirb. Thiere, p. 73, taf. i. fig. 15.

^{page 392 note ‡} Op. cit. p. 16.

^{page 392 note §} Archiv für Naturges. 1855, p. 150.

^{page 393 note *} Mém. de l'Acad. Roy. des Sc. de Belgique.

^{page 393 note †} Op. cit. pl. i. fig. 5.

^{page 394 note *} Op. cit. p. 12.—“En avant, ces vaisseaux aboutissent au-dessous des ganglions cérébraux, et, si nous ne nous trompons, ils se renflent là en vésicules qui semblent appartenir aux ganglions mêmes, et qui conduisent leur contenu à l'extérieur par un court canal excréteur aboutissant au fond de la fossette latérale.”

^{page 395 note *} Neueste Schriften, &c. Danzig, 1842.

^{page 396 note *} I am indebted to Mr Parfitt for living specimens of this species from Devonshire.

^{page 397 note *} Ann. des Sc. Nat. 3^me ser. tom viii. pl. ix. fig. 5.

^{page 397 note †} Op. cit. p. 12, &c.

^{page 398 note *} Op. cit. pl. iii. fig. 4.

^{page 398 note †} Zeitsch. f. w. Zool. xii taf. vii. figs. 3 and 4.

^{page 399 note *} Entwurf einer Syst., &c., p. 25.

^{page 399 note †} Boston Jour. Nat. Hist. vol. vi. No. 1, 1850Google Scholar.

^{page 399 note ‡} Zeitch. für wiss. Zool. bd. iv. 1853Google Scholar.

^{page 399 note §} Archiv für Anat. 1858.

^{page 401 note *} Archiv für Anat. &c. 1854, p. 75, taf. 4.

^{page 401 note †} Archiv für Anat. 1858.

^{page 402 note *} Op. cit. p. 182, pl. xx. fig. 8.

^{page 403 note *} Op. cit. pl. i. fig. 13.

^{page 403 note †} Op. cit. p. 13.—“La vésicule germinative ayant disparu, le vitellus s'organise, et, avant la ponte, nous avons trouvé des embryons converts de cils vibratiles.”

^{page 403 note ‡} Ann. Nat. Hist., 3d Ser. vol. xix. 1867, pp. 208–214, pl. v. figs. 3–17Google Scholar.

^{page 403 note §} Beobacht. über Anat. u. Entwickelung einiger Wirbellos. Seeth. Berlin, 1851, p. 111, taf. xi. fig. 8Google Scholar.

^{page 405 note *} Ann. Nat. Hist. 2d ser. vol. xvi. p. 259, pl. viiGoogle Scholar.

^{page 405 note †} Annales des Sc. Nat. 3d ser. tom. x. 1848Google Scholar.

^{page 406 note *} Zeitsch. für wiss. Zool. xii. 1863Google Scholar.

^{page 406 note †} Hist. Nat. du litt., &c. torn. ii. p. 128, pl. ii B. fig. 10.

^{page 407 note *} Ann. Nat. Hist. Oct. 1868.

^{page 407 note †} Christ. vid. Selsk. Forh. 1861, p. 56.

^{page 407 note ‡} Kongliga svenska Fregatten Eugen., &c., 1851–1853, p. 7, taf. iii. fig. 7.

^{page 407 note §} Dr Baird is now of the same opinion.

^{page 407 note ∥} Proc. Linnean Soc. vol. viii. p. 180Google Scholar.

^{page 408 note *} Die Borstenwürmer, &c. p. 105, taf. iii. fig. 5, 7–13, and taf. iv. fig. 1–3.

^{page 408 note †} M. Claparède probably refers to this species (in his rescent work “Les Annélides Chétopodes du Golfe de Naples”), under the name of Hermadion fragile.

^{page 408 note §} Archiv für Naturges. xxix. 1863Google Scholar.

^{page 408 note ‡} Linnean Trans. vol. xxv. p. 375, tab. 51, fig. 28.

^{page 408 note §} Nordiska Hafs-Annulater, 1865, p. 73, tab. 9, fig. 5.

^{page 408 note ¶} Beskrivelser og Jattagelser, &c. p. 62, pl. ix. fig. 25.

^{page 408 note **} Kongliga svenska Fregatten Eugenies, &c. p. 19, taf. v. fig. 28.

^{page 408 note ††} Cited by Malmgren, op. cit. p. 82.

^{page 409 note *} Les Annélides Chétopodes du Golfe de Naples, p. 99, pl. iv. fig. 4, and pl. v. fig. 1. I had described this new species under the name of S. buskii, but the unavoidable delay in the publication of the present paper gives M. Claparède's title the priority, if, as I am inclined to think, it refers to the same species.

^{page 410 note *} Die Borstenwürmer, &c. 1864, p. 120, taf. iv. fig. 4–7, and taf. v.

^{pagr 410 note †} Pow. Creat. vol. ii. p. 170, pl. xxiv. fig. 14.

^{page 410 note ‡} Nord. Hafs-Annulater, p. 93.

^{page 410 note §} Forhandlinger i Videnskabs-Selskabet, 1861, pp, 87, 88.

^{page 412 note *} Die Borstenwürmer, &c. pp. 190 and 199, taf viii.

^{page 412 note †} Troschel's Archiv für Naturges. 1855, p. 98.

^{page 412 note ‡} Annelés, vol. ii. 1865, pp. 100–102 and 106Google Scholar.

^{page 412 note §} Annulata Polychæta Spetsbergiæ, &c. 1867, p. 31.

^{page 412 note ∥} Beiträge zur Fauna Norwegens, &c. (Nov. Act. Acad. C. L. C. Nat. Cur. &c.), p. 168, tab. vii. fig. 1–4.

^{page 412 note ¶} Loud. Mag. Nat. Hist. vol. ix. p, 15, 1836Google Scholar.

^{page 412 note **} Zeitsch. für wiss. Zool. bd. xii. p. 107, taf. ix. figs. 32–36.

^{page 412 note ††} Beobach. über Anat. &c. p. 55, taf. xiv. figs. 1–7.

^{page 412 note ‡‡} Op. cit. vol. ii. p. 41.

^{page 413 note *} Die Borstenwürmer, &c. p. 256, taf. xi.

^{page 413 note †} Archiv für Naturges. 1866, and Annals N. Hist. March, 1868.

^{page 414 note *} Annelés, vol. ii. p. 63.

^{page 414 note †} Annulata Polychæta, &c. p. 39.

^{page 414 not ‡} Ann. Nat. Hist. 2d ser. vol. xvi. p. 31.

^{page 415 note *} Die Borsteirwürner, p. 234, taf. x.

^{page 415 note †} Annulat. Polychæta Spetzbergiæ, &c. 1867.

^{page 415 note ‡} Beiträge zur Fauna Norwegens, p. 164, taf. vii. fig. 12.

^{page 415 note §} Catalogue, &c. p. 192.

^{page 415 note ∥} Annulat. Polychæta, &c. p. 43, taf. vii. fig. 45 c.

^{page 416 note *} Quatref. Annelés, vol. ii. p. 28.

^{page 416 note †} Beobach. &c. p. 45, taf. xiii. figs. 36, 37, and Glanures Zootomiques, &c. p. 86, pl. vi. fig. 1.

^{page 417 note *} Prionognathus, Keferstein, Zeitsch. für wiss. Zool. vol. xii. p. 99, taf. viii. figs. 13–19.

^{page 417 note †} Annulat. Polychæt. &c. 1667, p. 62.

^{page 418 note *} Neue wirb. Thiere, &c. tom. i. ii. p. 114.

^{page 418 note †} Annelés, vol. i. p. 352.

^{page 419 note *} Op. cit. p. 88, pl. x. fig. 11.

^{page 419 note †} Annulat. Polychæt. &c. p. 82.

^{page 420 note *} Faun. Grœnland, p. 374.

^{page 420 note †} Annals Nat. Hist. May, 1866.

^{page 420 note ‡} Nordiska Hafs-Annukter, &c. 1865, p. 189; and Annulat. Polychæta, &c. p. 99, tab x. fig. 61

^{page 420 note §} Annulat. Polychæt. p. 99, tab. x. fig. 59.

^{page 421 note *} Nordiska Hafs-Annulater, p. 191.

^{page 421 note †} Fauna litt. Norveg. ii. p. 15, tab. 2, figs. 18–22.

^{page 422 note *} Annulat. Poly. Spetz. &c. p. 100.

^{page 422 note †} Cuv. Reg. An. iii. pl. xxii. fig. 4.

^{page 422 note ‡} Archiv für Naturges. 1860, p. 91, taf. iv. fig. 3.

^{page 422 note §} Archiv für Naturges. 1846, p. 163, taf. v. fig. 2 a, b, c.

^{page 422 note ∥} Annulat. Polychæta, &c. tab. xi. fig. 65 D.

^{page 422 note ¶} Proc. Lit. & Phil. Soc. Manchester, 1865.

^{page 422 note **} Ann. Nat. Hist. vol. xvi. 1855,,p. 310, pl. viii. figs, 7–12Google Scholar.

^{page 422 note ††} Nordiska Hafs-Annul. taf. xix. fig. 46 D.

^{page 423 note *} Fauna litt. Norveg. ii. p. 23.

^{page 423 note †} Nord. Hafs-Ann. p. 377.

^{page 423 note ‡} Pow. Creat. vol. ii. p. 191, pl. xxvii. figs. 1 and 2.

^{page 425 note *} Nord. Hafs-Annulat. p. 395, tab. xxiv. fig. 65.