304 SUMMAKY OF CURKENT RESEARCHES RELATING TO 



Notes on a Lake Erie Shrimp.* — W. B. Herms has made some 

 experiments on Fakemo/ietes exilipes Stimpson, the common shrimp of 

 Sandusky Bay, Lake Erie. It is strongly and positively phototactic, not 

 only to white light, but to red, green, violet, orange, blue, and yellow, 

 with a probable preference for red. 



Formation of Blood-corpuscles in Gammarids.j — L. Bruntz has 

 found in Gammarus pidex and Talitrus locusta that the blood-corpuscles 

 are formed in lymphoid organs in the front of the head extending 

 between the eyes, and quite distinct from the " frontal organs " of Delia 

 Valle. 



Female Gonads of Cypridina.| — Alfred Ramsch fills a gap by giving 

 a careful description of the ovary, oviduct, oogenesis, and external genital 

 parts of Gypridina mediterranm Coste. The paired ovaries lie on the 

 sides of the stomach-intestine, and belong to the saccular type. Both 

 ovary and oviduct are laterally compressed; the germinative area (a 

 syncytium) is confined to the side towards the median plane. From the 

 germinative area the ova pass by bulgings of the ovarian envelope into 

 follicles, where they grow. Thence after completion of their growth the 

 eggs pass back into the lumen of the ovary, and very rapidly via the 

 oviduct to the brood-chamber. The spermatozoa are disposed in egg- 

 shaped spermatophores. There is no receptaculum seminis. 



Parasitic Castration of Rhizocephala by Gryptoniscids.§ — Caullery 

 finds that Liriopsis has an indirect influence from a distance on the 

 ovary of Peltonaster, producing temporary atrophy, and that Danalia 

 parasitic on SaccuUna has a similar effect, inducing totiil degeneration of 

 the ova in process of maturation. In both cases the influence makes 

 itself felt from a distance, somehow saturating through the body. 



Annulata. 



Development of Saccocirrus.|l— Umberto Pierantoni gives an account 

 of the maturation, fertilisation, segmentation, embryonic and larval 

 stages of tSaccocirn/s papdJocercus Bobr. 



The gastrulation is intermediate between the epibolic and invaginate 

 modes. The entomeres proliferate within a precociously formed seg- 

 mentation cavity, without the ectomeres multiplying ; the invagination 

 is reduced almost to nil, the archenteron and blastopore being repre- 

 sented by a slight indimpling. 



The polar bodies are very large and penetrate into the segmentation 

 cavity, where they divide into larval coelomic corpuscles. 



These are two of the many interesting points in this communica- 

 tion. 



Peripheral Nervous System of Earthworm.^— Engelbert Dechant 

 gives a detailed account of this. The nervous elements of the earth- 



* Ohio Nat., vii. (1907) pp. 73-9 (2 figs.). 

 t Comptes Rendus, cxliii. (1906) pp. 1256-7. 

 X Arbeit. Zool. Inst. Univ. Wien, xvi. (1906) pp. 383-98 (1 pL). 

 § C.R. Soc. Biol. Paris, Ixii. (1907) pp. 113-15. 

 li MT. Zool. Stat.Neapel, xviii. (1906) pp. 46-72 (2 pis.), 

 t Arbeit. Zool. Inst. Univ. Wien, svi. (1906) pp. 361-82 (2 pis. and 2 figs.). 



