446 SUJ».1MARY OF CUKRENT RESEARCHES RELATING TO 



to a lesser degree on clinical observations. The author states the effects 

 of oophorectomy on the pregnant and non-pregnant uterns, on the other 

 ductless glands, and on the general metabolism. He discusses in succes- 

 sion the influence of thyroidectomy, removal of the parathyroids, removal 

 or injury of the pituitary, thymectomy, and the removal of the supra- 

 renals. He considers the relation of the pancreas to the other organs 

 of internal secretion ; the influence of various hormones, including those 

 of the foetus, on mammary activity. 



The influence of the ovary on the general metabolism is related to 

 and dependent on its primary reproductive functions. The thyroid, 

 pituitary, and suprarenals influence the development and subsequently 

 preserve the integrity and activity of the genitalia. Others — the 

 thymus, and possibly the pineal — appear to prevent sexual precocity. 

 Moreover, all the endocritic organs, acting in harmony, control the 

 metabolism in response to the necessities of the genital functions ; in 

 addition, they adapt the whole organism to the needs of the situation, and 

 regulate the secondary characteristics, both physical and psychical, to 

 suit the requirements of the individual. Once, however, the reproductive 

 organs are removed or undergo atrophy, the genital functions of the 

 rest of the endocritic system cease, and the metabolism is readjusted. 

 Contrariwise, insufficiency of the thyroid, pituitary, or suprarenals, may 

 cause the cessation of the genital functions with atrophy of the uterus. 

 The individual metabolism and the reproductive metabolism are 

 absolutely interdependent. This thesis is then corroborated by evidence 

 from pathological conditions. 



Collar Cavities of Larval Amphioxus.* — K. M. Smith and H. G. 

 Newth find that the space into which the right collar cavity opens as it 

 sweeps downwards towards the mid-ventral line is the splanchnocoel, and 

 not, as MacBride supposed, a distinct cavity lying external to the 

 splanchnocoel, which later became the cavity of the atrial fold (van 

 Wijhe's " pterygocoel "). MacBride f accepts the conclusion of the 

 authors, whose material he has examined. A re-examination of his own 

 preparations leads him to believe that the septum which he believed to 

 divide the splanchnocoel from another cavity external to it is the parietal 

 wall of the coelom, which in the process of preparation had become 

 separated from the ectoderm. The facts elucidated by Smith and Newth 

 enable us to compare the collar cavity of Amphioxus directly with the 

 mandibular cavity of the embryos of Petromyzon and the Elasmobranch 

 embryo. 



6, Histolog-y. 



Amitosis in Cells in Vitro. $ — C. C. Macklin has studied cultures 

 of tissues from chick-embryos (two to ten days old). They were kept in 



* Quart. Journ. Micr. Sci., Ixii. (1917) pp. 243-51 (1 pi,). 

 t Quart. Journ. Micr. Sci., Ixii. (1917) pp. 249-50. 

 X Biol. Bull., XXX. (1916) pp. 445-62. 



