616 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Platyhelminthes. 



New Species of Cephalogonimus.* — AV. S. Nickerson describes G. 

 vesicaudus sp. n., from the intestine of soft-shelled river-turtles, Aspido- 

 nectes and Amyda. The peculiarity of the genus is the position of the 

 genital aperture at the extreme anterior end of the body in front of the 

 oral sucker. The new species differs from the type species G. Unoiri in 

 the possession of a caudal vesicle, the absence of an oesophagus, and the 

 oblique position of the testes. The author gives details in regard to the 

 minute structure. 



Incertae Sedis. 



Polyzoa of Clare Island. f — A. R. NicholLs reports on the collection 

 of Polyzoa made during the Clare Island Survey. A stone from off " The 

 Bills" bore fourteen species, and another small stone bore eleven. Seventy- 

 five marine species are recorded, and five varieties. Five fresh-water 

 species are noted, and Membranqwra memhranacea was found on weed 

 in the stream of brackish water draining Furnace Lough. 



New Loxosomas.J — Richard Assheton describes two new species of 

 this genus, which is remarkable among Polyzoa in having the lopho- 

 phore placed more or less obliquely to the main axis of the stalk instead 

 of being at right angles as in other Polyzoa, and in being solitary, for 

 the buds drop off before they have reached any great size. The species 

 occur as commensals on other organisms or on the tubes inhabited by 

 other organisms. One of the new forms, L. loxalina, was found along 

 with a Maldanid worm, in the Sound of Mull ; the other, L. saltans, was 

 found in the tube of a Maldanid worm, Glymene ebiensis, on the Skye 

 shore of the Kyle of Loch Alsh. 



The body and the lophophore of L. loxalina are beset with four pairs 

 of deeply placed ectodermal organs along the lateral margins. Thei'e 

 are two or fewer in'L. saltans. The specific name of the latter refers 

 to its habit of locomotion by jumping, in which the four large tentacles 

 take part. In L. saltans there are two very distinct proximal diverticula, 

 which appear to secrete some substance, probably digestive, into the gut. 

 The excretory organs of this species are lophophoral and body kidneys 

 — large vacuolated cells which perhaps lie in contact with ducts, and 

 there are other vacuolated cells which presumably burst into the cavity 

 of the rectum. There is a pair of gonads in L. loxalina, a single median 

 gonad in L. saltans. 



Echinoderina. 



Heterog-eneous Hybridization in Echinoderms.§ — A. R. Moore has 



followed up Loeb's experiment of fertihzing sea-urchin eggs witli starfish 

 spermatozoa. The success of Loeb's experiment depended upon tlie 

 fertilization taking place in hyper-alkaline sea water, i.e. sea water to 



* Zool. Jahrb., xxxiii. (1912) pp. 249-56 (1 pi.). 



t Proc. Irish Acad., xxxi. (1912) Clare Island Survey, Part 53, pp. 1-14. 

 X Quart. Journ. Micr. Sci., Iviii. (1912) pp. 117-43 (2 pis. and 4 figs.). 

 § Univ. California Publications (Physiology) iv. (1912) pp. 109-14. 



