584 SUMMARY OF CURRENT RESEARCHES RELATING 10 



of appendages ; the oesophagus is lined by colnmnar epithelium ; the 

 mid-gut is devoid of obvious muscles ; the testes are small and cylin- 

 drical. It may be referred, along with Ive, to the family Chondra- 

 canthidse, but this reference must remain provisional until the stages 

 between the nauplius and the adult have been found. 



Annulata. 



Marine Oligochgete from Clare Island.* — R. Southern describes 

 Grania mar kola g. et sp.n., a remarkable new form with a very interesting 

 resemblance to Michaelsen's Enchytraeus mo^iochsetus found on the shore 

 of South Georgia. In Grania the seta3 are straight and thick, wide at' 

 the inner end, absent from the anterior region, a single ventral pair in 

 the middle region, joined in the posterior region by a dorsal pair. 

 There are no dorsal pores. The dorsal vessel rises behind the clitellum. 

 There is no cardiac body. The spermathecse communicate with the 

 oesophagus. The pharynx is dorsal. It occurred in depths of as much 

 as 24 fathoms, and is the first 01igocha3te found below low-water mark. 



Structure of Stratiodrilus.f — W. A. Haswell describes this Histrio- 

 bdellid {Stratiodrilus novse-Jwllandise)^ which is about 1-1*5 mm. in 

 length when full-grown. It is a more highly organized animal than 

 ffistriobdeUa, as is shown in the more differentiated muscular and 

 nervous systems, and in the presence of three pairs of cirri with their 

 sensory cilia. The excretory system is widely different. The tentacles 

 in Histriohdella are unjointed, in Stratiodrilus 2-jointed ; the anterior 

 limbs are non-retractile in the former, freely retractile in the latter ; 

 Histriobdella has no definite tail region, while in Stratiodrilus this region 

 is sharply marked off from the trunk, and its body-cavity is cut off from 

 that of the latter by a partition. The animal lives in the gill-cavity of 

 the crayfish {Astacopsis serratus) ; it walks and swims by peculiar move- 

 ments of the hind-limbs. Haswell deals in particular with the body- 

 cavity, the jaws and digestive system, the nephridia, the nervous system, 

 and the reproductive system of the female. 



Nematolielininthes. 



Nematodes of Lake Geneva. | — B. Hofmanner gives an account of 

 the free-living Nematodes of Lake Geneva. He has found no fewer 

 than 4?) species, 34 littoral, and 9 from deep water. Eight new species 

 are described. Of the 26 littoral species, 8 are found in sandy areas 

 without any green vegetation. It seems likely that the littoral forms 

 are, or have arisen from, terrestrial forms brought to the lake by birds, 

 and that there has been a migration from the shallow water to the 

 depths. Three species are viviparous, but many of the forty oviparous 

 species liberate eggs which have reached the gastrula-stage. 



* Proc. Irish Acad., xxxi. (1913) Glare Island Survey, pt. 48, pp. 1-14 (1 pi.), 

 t Quart. Journ. Micr. Sci., lix. (1913) pp. 197-226 (4 pis. and 1 fig.). 

 X Kev. Suisse Zool., xxi. (1913) pp. 589-658 (2 pis.). 



