ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 233 



with the presence of the mechanical factors determining them." The 

 pharyngeal bursa in man cannot be regarded as a structure of funda- 

 mental significance, essential to the development of the pharyngeal 

 tonsil as Schwabach maintained. If it were essential, its presence might 

 l)e reasonably expected in the pharyngeal roof of all forms which possess 

 a well-developed pharyngeal tonsil. The calf has the latter, but a 

 pharyngeal pocket corresponding to the bursa in man does not regularly 

 develop. In the pharyngeal regions of embryos of the types discussed, 

 an outstanding feature common to the three is a close relationship 

 between the fibres of the fascia pharyngobasilaris and the pharyngeal 

 epithelium. J. A. T. 



Influence of G-onads in White Rats.— Carl R. Moore {Journ. 

 Exper. ZooL, 1919, 28, 137-60, 5 figs.). On the somatic side the early 

 spayed female rat with implanted testis increases in weight, but it is not 

 that the testis has any influence upon growth, it is rather that removal 

 of the ovary allows a relative increase in weight. The same is true in 

 regard to body length. The presence of the ovary tends to retard 

 growth. Changes in hair and fat deposition and some other features 

 do not seem to the author to prove a transformed sexual nature, but 

 rats are not good material for this kind of inquiry. " The psychic 

 behaviour of the animals, however, absolutely distinct in itself, lends 

 great weight to the idea of a transformed sexual nature," such as 

 Steinach insists on. J. A. T. 



Possibility of Differential Selection of Germ-cells in Fowl.— 

 C. H. Danforth {Froc. Amer. Ass. Anatomists in Atiat. Record, 1919, 

 16, 147-8). If the germ-cells produced by a heterozygous animal fall 

 into several classes, may they not react differently to chemically and 

 physically changed surroundings, or at least show somewhat different 

 potentialities in their competition with each other ? To test this, cocks 

 heterozygous in regard to brachydactyly, Polydactyly, colour, and shape 

 of comb were mated with hens homozygous for these features in their 

 recessive forms. A record was made of the numbers in each class of 

 young produced before and after treating the males with alcohol. The 

 data thus obtained indicate that the administration of alcohol by inhala- 

 tion alters the proportion of certain classes of chicks produced. This 

 suggests that a mildly toxic agent may select between germ-cells on the 

 basis of the Mendelian determiners which they carry. Incidentally it is 

 observed that " a recognition of the fact that the probability that a 

 germ cell will function is in some degree dependent upon the deter- 

 miners which it carries, may lead to a satisfactory explanation for 

 orthogenesis." This suggestion should be correlated with Weismann's 

 germinal selection. J. A. T. 



Interstitial Cells in Gonads of Fowl. — H. D. Good ale (Ajiat. 

 Record, 1919, 16, 247-50, 4 figs.). Evidence is submitted that the 

 granular interstitial cells are really eosinophil leucocytes. They were 

 found in relative abundance in the ovary and in degenerating tubules 

 (not in normal portions) of the testis. Precisely similar cells may be 



