ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 259 



repeated at thirty-second intervals. Repeated contact-stimulation of 

 the posterior end induces first a gradual increase in activity, followed 

 by a gradual decrease, ending in complete depression. The effects of 

 strychnin, nicotin, cocain, chloretone, and magnesium sulphate, appear 

 essentially the same as those produced in higher animals. Carbon 

 dioxide, mono-potassium, phosphate, and lactic acid produced at first a 

 much increased activity, followed by complete depression. The internal 

 state of the leech exercises a profound influence on its behaviour, 

 hunger producing a greater relative responsiveness, satiety a greater 

 sluggishness The presence of a superfluity of foodstuffs within the 

 body may lead to the accumulation of intermediate metabolic products, 

 which may react on the animal as do the fatigue substances. 



Nematohelminthes. 



Antarctic Nematodes.* — X. A. Cobb reports on the free-living 

 Nematodes collected at Cape Royds by the Shackleton Expedition— 

 twenty-five new species and two new genera— Aplectus (near Plectus) 

 and A ustronema (near Monliystera). There appears to be great abund- 

 ance of these Nematodes, mostly vegetarian. The Antarctic species are 

 on the whole somewhat smaller than those of warmer seas, but they are 

 very like them. They seem to be equally prolific. In Terschdlingia 

 polaris there is marked dimorphism in the spermatozoa ; indeed, it is 

 suggested that three members of the spermatid complex may correspond 

 to " polar bodies." The author also suggests that there are dimorphic 

 species with free-living and parasitic phases. 



Marine Nematode in Sub-alpine Swiss Lakes. f — B. Hofmanner 

 makes a careful comparison of Monohystera setosa Butsckli and M. dubia 

 Blitschli, and finds that the former must include the latter. It has been 

 found in the Baltic, in the North Sea, in the Botanic Garden at Frank- 

 fort, and now it turns up in sub-alpine lakes in Switzerland. 



Fresh-water Nematodes.! — H. Micoletzky gives a systematic account 

 of no fewer than fifty-seven fresh-water Nematodes from the Lake of 

 Lunz, in the East-Alps. He also discusses some of the variations 

 observed, the young stages, the mode of life, aud the reproductive 

 relations. In five cases no males were found. As Maupas observed, 

 parthenogenesis and hermaphroditism occasionally occur. All the forms 

 seem to be vegetarian, eating algae and parts of plants. Infection with 

 parasites is very rare. 



New Nematode from a Buzzard. § — L. G. Seurat has recently re- 

 ferred the form known as Spiroptera leptoptera, from birds of prey, to 



* Antarctic Marine Free-living Nematodes. Baltimore, 1914, pp 1-33 (25 figs.), 



t Zool. Anzeig., xlii. (1913) pp. 413-18 (4 figs.). 



t Zool. Jahrb., Abth. Syst., xxxvi. (1914) pp. 331-546 (11 pis. and 1 map). 



§ C.R. Soc. Biol. Paris, lxxvi. (1914) pp. 427-9 (3 figs.). 



