SUMMARY OF CURRENT RESEARCHES 



RELATING TO 



ZOOLOGY AND BOTANY 



(principally invertebrata and cryptogamia), 



MICROSCOPY, Etc.* 



ZOOLOGY. 



VEBTEBBATA. 

 a. Embryology, -f 



Embryonic Appendage of Claws of Amniota.J — W. E. Agar finds 

 in the embryos of the armadillo Tolypeutes and other Mammals, as also 

 in those of cbick and lizard, that the claw includes besides the dorsal 

 " Krallenplatte " and the ventral " Krallensohle," a third portion, the 

 neonychium. This is an entirely provisional embryonic structure, which 

 turns the tip of the claw from a hard scratching point into a smooth 

 rounded surface. It is highly probable that its function is to protect 

 the embryonic membranes from being torn by the claws during move- 

 ments of the embryo. As the time for birth or hatching approaches, 

 the neonychium begins to break away from the rest of the claw, and is 

 probably in most cases rubbed off by contact with the ground directly 

 the embryo emerges, as was shown to be the case in the chick. 



Study of Darwinism.§ — J. Arthur Thomson has published six lec- 

 tures on Darwinism delivered in South Africa in the autumn of 1909. 

 They form an introduction to the study of the theory of organic evolu- 

 tion, and bear the following titles : What we Owe to Darwin ; The Web 

 of Life ; The Struggle for Existence ; The Raw Materials of Progress ; 

 Facts of Inheritance ; Selection : Organic and Social. It was the chief 

 aim of the lectures to explain the gist of Darwinism — what problems 

 Darwin set himself to solve, and what solutions he arrived at, and to 

 indicate what progress has been made as regards the problems of Organic 

 Evolution since Darwin's day — what has been added to Darwinism, what, 



* The Society are not intended to be denoted by the editorial " we," and they 

 do not hold themselves responsible for the views of the authors of the papers 

 noted, nor for any claim to novelty or otherwise made by them. The object of 

 this part of the Journal is to present a summary of the papers as actually -pub- 

 lished, and to describe and illustrate Instruments, Apparatus, etc., which are 

 either new or have not been previously described in this country. 



t This section includes not only papers relating to Embryology properly so 

 called, but also those dealing with Evolution, Development, Reproduction, and 

 allied subjects. J Anat. Anzeig., xxxv. (190j) pp. 373-80 (7 figs.). 



§ Darwinism and Human L if e : the South African Lectures for 1909. London 

 (1909) 245 pp. 



