462 SUMMARY OF CUHKENT KESEARCHES RELATING TO 



weight) by underfeeding. In adult rats during acute and chronic 

 inanition, the reduction in the size of the parathyroids is nearly 

 proportional to that of the body as a whole. In minute structure the 

 parathyroid is relatively more resistant than the thyroid to inanition. 

 The changes in the structure of the epithelial cells are somewhat similar 

 to those described for the thyroid, though in general less marked. 



c. General. 



Effects of Atmospheres Rich in Oxygen."' — Howard T. Karsner 

 has subjected rabbits to high oxygen partial pressure (80 to 90 p.c.) 

 under ordinary barometric pressure. In twenty-four, or, more commonly, 

 fortj -eight hours there resulted congestion, edema, epithelial degenera- 

 tion and desquamation, fibrin formation, and finally pneumonia, probably 

 of irritative origin and to be described as a fibrinous bronchopneumonia. 



Mammae of Rat.f— J. A. Myers has studied the growth and the 

 gross relations of the ducts and nipples of the albino rat from birth to 

 the tenth week. The number of glands varies between ten and thirteen, 

 the normal being sis pairs. Only one primary duct is present in each 

 gland : its branching is often dichotomous ; anastomoses sometimes 

 occur between the ducts of a single gland ; there is considerable indi- 

 vidual variation in development ; the characteristic distribution and 

 ramification of the ducts apparently depend upon the space available 

 for their growth ; the growth and branching of the ducts goes on at 

 an unusually rapid rate about the ninth week, probably corresponding 

 to the age of puberty ; a distinct lumen is present at birth in all the 

 ducts distal to the intra-epidermal portion of the primary duct ; at 

 the end of the second week the lumen extends to the surface of the 

 nipple. 



Abnormality in Frog. J — R. W. Harold Row describes a case of 

 symmetrically abnormal hind feet in Rami temporaria, which showed 

 an absence of the first digit. The calcar was present normally, and 

 there was no trace of any mutilation. 



Abnormalities in Vascular System of Frog.§ — Walter E. Collinge 

 notes tlie occurrence of twenty-two abnormalities in about 500 specimens, 

 and describes the ten most important of these. Some are of interest 

 in illustrating the persistence of embryonic stages, while others may be 

 regarded as reversions to ancestral conditions. Figures are given of 

 a persistent caudal vein, of a renal-portal vein continuous with the 

 inferior vena cava, of a looped renal-portal, of a double renal-portal, 

 of a persistence of the embryonic right posterior cardinal sinus, of the 

 persistence of the connexion with the heart of the anterior abdominal 

 vein on both sides, and so on. 



* Journ. Exper. Med., xxiii. (1916) pp. 149-70 (4 pis.). 



t Amer. Journ. Anat., xix. (1916) pp. 353-88 (4 pis. and 6 figs.). 



I Proc. Zool. Soc. London, 1916, pp. 87-9 (1 fig.). 



§ Journ. Anat. Physiol., 1. (1915) pp. 37-42 (12 figs.). 



