The Japanese observers Ido, Hoki, Ito and Wani (1916) state that in Infectious Jaundice the infective organism—the Spirochaeta icterohaemorrhagiae—is transmitted probably from rats to man by means of the urine of rats, directly or indirectly.

Amblyomma dissimile Koch is well known to science and previous accounts of its biology have already appeared. Newstead (1909) made some observations on its habits in Jamaica. Hooker, Bishopp, and Wood (1912) give an exact account of its life cycle worked out in confinement in the Southern United States of America. These authors do not refer to the occurrence of parthenogenesis in this species.

Part I of this paper, which dealt exclusively with the females, appeared in Parasitology, VIII. 262. After examining some dozens of dogfish each month for the previous three years I, at length, on April 2nd 1918 obtained from two separate dogfish caught during the preceding week at Plymouth, three females of Lernaeopoda scyllicola which were accompanied by males.

Habitat and Record. On 10. iv. 1918 my attention was called to five specimens of Lernaeopoda occurring on Scyllium canicula obtained at Plymouth. The largest copepod was attached outside and about one inch ventral to the left spiracle. The other four were deeply concealed within the left nasal groove, so that the nasal flap had to be cut away in order to detach the parasites. These specimens exhibit characters of their own which seem to combine those of other established species. The most striking modification is that the ends of the attaching “arms” (2nd maxillae) are expanded into large discs on either side of a vestigial bulla, thus recalling L. bidiscalis Kane, 1892, though that species is described as possessing discs of a different conformation, and as having no bulla. In other respects they agree more with L. musteli Thomson, 1899, notably as to their small size, and the proportion of the arms to their trunk. But to these points I do not attach much importance, since both may be due to the confined space in which the parasites are domiciled.

The existence of trypanosomiasis amongst the ruminants of Turkestan has been suspected for many years, but the first definite record is that of Liihs (f906) who discovered Trypanosoma theileri in the blood of cattle in Transcaucasia. This was followed by the discovery of the same parasite in the Trans-Baikal Region (Dudukaloff), the Don Province (Stolnikoff) and in the Pskov and Vitebsk Governments (Yakimoff and Bekensky). Wrublewski found this trypanosome in the blood of bison from the Bieloviejsky forests and later it was discovered by Yakimoff in Turkestan.

In the autumn of 1917 the writer received several letters from Mr L. C. Peters describing his experiences with flies hibernating in a large and very old house, situated in a large park at Frampton, near Kirton, Boston, Lincolnshire. Mr Peters' attention was directed first to the matter towards the end of October. On removing the window sashes the frames were found “black with flies.” After fumigation a bucketful of dead flies was removed from a single window frame, and about six bucketfuls from other infested windows. Only one side of the house was affected, but on that side the flies were found in the window frames on all three stories. “Ladybirds” were also present in large numbers.

In the following pages I shall endeavour to describe the present state of our knowledge of Bilharziasis in Natal and the result of some personal observations extending over the last seven years. The investigations of the Bilharzia Mission to Egypt have drawn attention to the various forms of cercariae which infest several species of fresh-water snail in African rivers. The cercariae which give rise to Bilharzia disease in Egypt are furcocercous cercariae, i.e. they possess a. tail which is divided for a greater or shorter portion of its length. They are characterised, further, by the absence of a pharynx at the commencement of the oesophagus. Similar cercariae are present in one of the species of fresh-water snail which abounds in the infected areas of Natal.

During the months of September, October, November and December 1917 I collected 1250 different specimens of fresh-water snails from various parts of the Transvaal, more especially from the sources of the Vaal and Crocodile rivers. All the larger specimens I submitted to microscopic examination for possible infection with cercariae. From the mud at the bottom of the Mooi river at Potchefstroom, which is a tributary of the Vaal, I came across some very finely preserved specimens of Unio caffer Krauss, a large number of which contained small pearls attached to the shell. The amount of lime in the bed of this river probably accounted for the perfect state of the umbones of these Uniones. Amongst the small stones at the bottom of the river I collected some remarkably large specimens of Corbicula radiata Parreyss. The river also contained some specimens of Pisidium, a much smaller variety, not yet identified. On the decomposing rushes at the edge of this river there were numerous specimens of Ancylus, for which Mr Henry C. Burnup has suggested the name Ancylus cawstoni; I have seen similar specimens at Klerksdorp and in the Hex river at Kustenburg, a branch of the Little Crocodile. All these specimens were free from cercarial infection.

In my previous paper on the body louse (1916) many points of morphological interest were necessarily left in abeyance and mention was made that certain statements in it were open to correction. Further work has rendered correction possible. While working in France, to ascertain whether Pediculus humanus was a carrier of the spirochaete of Weil's disease, opportunity was taken to investigate those organs of the louse in which the spirochaete might lodge and the afferent and efferent channels through which it might pass. The enquiry did not demonstrate the presence of the spirochaete in the body louse, but incidentally a detailed knowledge of the mechanism of feeding was obtained and is here presented. Since the main conclusions of this paper were reached (December, 1916) I have read Harrison's paper, “A Preliminary Account of the Structure of the Mouth-Parts in the Body-Louse,” and while much of the following verifies his statements, we differ on certain important points regarding the structure of the mouth-parts and musculature.

The animal under consideration belonging to the family Lernaeopodidae was taken on a codling (Gadus morrhua), 13 ins. in length, caught at Plymouth several years ago, and preserved in formalin since that date. Although about twenty-six valid species of Clavella have been either recorded or described in detail, the subject of the present paper differs from them all in combining several of the more prominent characters of other species, notably the extreme length of the backwardly-arched cephalothorax taken together with the reduction of the “arms” (second maxillae) and their expansion into a disc so that the “bulla” or button appears to be almost directly affixed to the body. For this species I accordingly propose the name Clavella sciatheric.