638 SUMMARY OF CURRENT RESEARCHES RELATING TO 



migration on the part of the ccntrosomc. This points to a fundamental 

 polarity in epithelial cells. 



Comparative Anatomy of Cervical Sympathetic System.* — Dr. M. 

 Jaquet has taken a comparative survey of this portion of the nervous 

 system, from the appearance of ganglia without a cord in the larval 

 lamprey to the state of affairs in man. A somewhat primitive state is 

 represented in some fishes, where the sympathetic is related to five 

 cranial nerves much as it is to the rachidian nerves ; a condensation 

 gradually occurs, marked finally hy the establishment of a single superior 

 cervical ganglion. Although the pneumogastric has at first to discharge 

 work which in higher forms falls to the sympathetic system, it is far 

 from losing influence as the latter increases. It cannot be denied, how- 

 ever, that there is a distinct correlation in their degree of development. 



c. General. 



Quantitative Study of Variation.! —Prof. C. B. Davenport has done 

 a useful service in presenting a history of the development of this study, 

 from Quetelet and Galton to Pearson and Weldon. " The quantitative 

 study of biology, the modern impulse to which we owe to Galton, has 

 been furnished with good methods by Pearson. Already the applica- 

 tion of these methods has borne fruit in our knowledge of the types 

 of biological frequency curves, and their change with changing place 

 and environment. The idea of correlation has received a precise 

 definition. The results of experimentation have been quantitatively 

 expressed. The role of natural selection, the method of evolution, and 

 the laws of inheritance, are being discovered. Already we are able to 

 predict greater results from the quantitative method in biology, 

 -especially when combined with experimentation, than any which have 

 yet appeared." 



Accessory Adrenal Bodies in Mammals. * — Josef Wiesel found 

 accessory adrenals in connection with the epididymis in 79 per cent, of 

 new-born male infants, but after birth they gradually disappear, and 

 later become vestigial. They have no medulla, but the cortex has the 

 usual structure. In the rat, accessory adrenals of similar structure are 

 frequent, and undergo hypertrophy if the main glands be extirpated. 

 Under these circumstances they do not develop a medulla, which is an 

 additional proof that the functions of the two regions of the gland are 

 different. Probably the function of the medulla is taken on by some 

 other part of the sympathetic, as it chiefly consists of nervous elements 

 of the sympathetic. 



Breeding-habits of Xenopus lsevis.§— E. J. Bles finds that at the 

 breeding-season in this frog, the whole inner side of the arm in the 

 male, from the axilla to the tips of the fingers, develops minute pointed 

 spines, and becomes darkened in colour. The roughening is present on 

 all that part of the arm aud hand which presses against the female, and 

 is found on the back and not the palm of the hand. The rnalo produces 



* Bull. Soc. Sci. Bucarest, x. (1901) pp. 240-302 (13 pis.). 

 t Proc. Amer. Ass. Adv. Sci., 49th Meeting, 1900, pp. 197-203. 

 + SB. Akad. Wiss. Wien (sec. iii.), cviii. (1899) pp. 257-S0 (1 \l.\ 

 § Proc. Cambridge Phil. Soc, xi. (1901) pp. 220-2. 



