Previous work has shown a sex difference dependant upon œstrogen-androgen balance, in the rate of clearance by the fowl liver of intravenously administered sodium bromosulphthalein. Further observations reported here indicate an apparent rapid fluctuation of the Œ-A balance which takes place in immature chickens, both sexes snowing what is interpreted as hyperœstrogenization about the age of twelve weeks. Attention is drawn to other evidence that profound metabolic and hormonal changes occur at this stage. The effect of exogenous sex-hormones on the clearance rate of BSP has been further studied, particularly the influence of extra androgen on adult males with aberrant clearances unassociated with liver lesions. More evidence for the relation between the rate of BSP clearance and the Œ-A balance is provided by the study of the effect of cessation of ovulation on the clearance, and the effect of the development of virilizing tumours at the site of the rudimentary right ovary after left ovariectomy. Other changes which confirm hyperœstrogenization as assessed by the BSP clearance test are (a) decrease of the packed cell volume, (b) the development of a precipitable phospholipid in the plasma, (c) renal vascular changes, (d) adrenal cortical hyperplasia, (e) a frequent association with oviduct ligament “fibroids” and persistent cystic right oviducts.

Evidence is presented that, in fowls, as in a number of mammals, intravenously administered sodium bromosulphthalein is excreted by the liver into the bile in several forms. These metabolites are not glucuronides, esters or sulphates, and in the fowl do not have the chromatographic mobilities or other characteristics of any of the amino acids described as conjugating with BSP in mammals. In all, three forms of BSP are detectable in fowl bile after administration of the dye, one, with the highest Rf. is unchanged BSP, the others are associated with ninhydrin positive material, and have lower Rf. values. Conjugation has been studied in young chickens and in adults, and the effects of sex hormones, cortisone and liver damage have been assessed. It is shown that a proportion of the injected BSP may be retained for some time in the liver as a colourless form, so that only prolonged alkaline hydrolysis of liver extract and homogenate results in its liberation as a detectable coloured form. The significance of this, and the effect of sex hormones in influencing the amount of conjugation and thus possibly affecting the rate of liver clearance of BSP is discussed, and evidence is presented that there exists an apparent inverse relationship between the amount of œstrogen as assessed by BSP liver-clearance test and the relative proportions of the two BSP conjugates in the bile. Also direct relationship may exist between the amount of œstrogen and the proportion of colourless BSP found in the liver.

The chromosome constitution of the bisexual beetle Ptinus clavipes Panzer (2n = 18) and of its gynogenetic form P. clavipes f. mobilis Moore (3n = 27) have been investigated. The triploid mobilis lives in close association with the bisexual species and mates freely with the males. Eggs from virgin females never pass beyond the metaphase stage and successful completion of maturation is dependent on the presence of sperm. An endomitotic split is apparent in prophase chromosomes and leads to the formation of twenty-seven pseudobivalents which undergo a pseudomeiotic division. Only one maturation division has been observed. Although the fate of the activating sperm has not been resolved it is thought that sperm nuclei give rise to isolated haploid nuclei in some eggs and interfere with normal cleavage in others. Since the triploid form may also mate with males of Ptinus pusillus Sturm and P. fur. L. with reduced numbers of progeny the affinities of the gynogenetic form is discussed. This is the only known case of gynogenesis in Coleoptera.

From a faunistic survey in Scottish waters, concentrated mainly in the sea lochs of the north-west coast and in the deep water in the North Sea off the east coast, thirty-two species of polychætes are listed which have not previously been recorded from these areas. Seven of the species are new records for British coastal waters or for the North Sea.

The immature stages of C. circumscriptus Kieff. are found in the mud of most Scottish salt marshes. The life cycle has been studied by means of laboratory cultures and by observation and periodic sampling at a salt marsh near Dumbarton. Data are given concerning the life cycle in the laboratory and out of doors. In the field there are two generations a year.

In captivity the female lays a single large batch of eggs which adhere to the substrate by means of structures on the chorion. The eggs and the manner of oviposition and hatching are described. Descriptions of the larvae, supplementing those of previous authors are given. The first instar differs from older larvae in possessing a retractable prothoracic proleg, and is more sluggish in its movements, probably remaining near the oviposition site until the first ecdysis. Before pupation the larva comes to the surface. This is necessary for successful pupation, enabling the pupa to breathe and to form the buoyancy space. The pupa buries itself in the mud emerging only under flooded conditions to float on the surface or prior to ecdysis.