438 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Annulata. 



Maturation in Allolobophora fcetida.* — K. Foot and E. C. Sfcrobell 

 give a number of facts regarding the prophase and metaphase of the first 

 maturation spindle of Allolobophora, only a few of which can be quoted. 

 Daring the prophases there is a marked change in the structure of the 

 cytoplasm, a decrease in the size of the egg, and an increase in the 

 amount of the substance between the egg membrane and the outer 

 membrane. The centrioles are first seen at opposite poles of the ger- 

 minal vesicle, indicating that they arise independently. The nucleolus 

 is intact at this stage ; the centrioles do not arise from it. The func- 

 tional value of the nucleolus is probably confined to the nucleus. There 

 is some evidence to support the theory of the individuality of the 

 chromosomes, and in general the authors' observations on the division 

 of the chromosomes appear to confirm the work of previous workers 

 on other forms. 



Phagocytary Resorption in Seminal Vesicles of Lumbricus.f — 

 L. Brasil points out that the presence of numerous amoebocytes in the 

 seminal vesicles of Lumbricus is normal and constant. They exercise 

 an intense phagocytary resorption upon the unutilised reproductive 

 elements, and also upon their empty cytophores. They completely 

 clean these elements after emissions. Their action upon the cysts of 

 Gregarines is secondary, and these are not the direct cause of their 

 presence. 



Setal Pockets in Polychaets.f — A. Schepotieff has studied these in 

 Nereis cultrifera, Protula intestinum, Nephthys scalopendroides, and 

 Eunice viridis, the palolo-worm. There is no great difference between 

 the setal pockets in those Polychasts and the similar structures in Oligo- 

 chasts. Typically, each seta is the product of a single formative cell, 

 which lies at the base of an epithelial invagination — the setal pocket. 

 The differences in the various forms, and as regards the various kinds of 

 setae, are described. 



New Species of Sea-Mouse.§— J. Percy Moore describes Aphrodite 

 hastata sp. n., from eastern Massachusetts, which differs in many and 

 striking characters from A. aculeata, e.g. in the altogether different form 

 of the large notopodial spines. It is really less closely related to 

 A. aculeata than to other species of the genus, and probably finds its 

 nearest ally in A. japonica Maren., which is widely distributed in the 

 Northern Pacific. There is doubt, therefore, where the true A. aculeata 

 really occurs on the American Atlantic coast, as has been generally 

 assumed. 



Regeneration in Protodrilus.|| — N. Lignau has studied the re- 

 generation of the anterior and posterior regions of the gut, and the 



* Anier. Journ. Anat., iv. (1905) pp. 199-243 (9 pis.). 

 t Comptes Rendus, cxl. (1905) pp. 597-9. 



\ Zeitsclir. wiss. Zool., lxxvii. (1904) pp. 586-605 (3 pis. and 7 figs ). 

 § Proo. Acad. Nat. Sci. Philadelphia. 1905, pp. 294-8 (4 figs.). 

 Mem. Soe. Nat. Nuuv-Russie, xxvii. (1905) pp. 1-40 (2 pis.). 



