594 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Bengal Polyzoa.* — Nelson Annandale describes a new Ectoproctous 

 Polyzoon, Victorelhi bengalensis sp. n., from brackish ponds at Port 

 Canning, Lower Bengal, and a new Entoproctous form, Loxosomatoides 

 colonialis g. et sp. n. The diagnosis of the new genus is : — " Colonial, 

 deciduous Entoprocta arising from a creeping stolon ; the calyx, 

 separated from the stalk by a diaphragm, with a slanting or vertical 

 lophophore and bearing on its aboral surface a chitinous shield, which 

 is absent from the stalk." The closest affinities of Loxosomatoides are 

 probably with Myosoma. 



Echinoderma. 



Habits of Starfish. f — Georges Bohn finds that starfishes (Asteria* 

 rubms) from the rocky regions of the Channel behave differently as 

 regards light from those which live in sandy parts of the Arcachon 

 basin. The former move away from the light into the shade ; the 

 latter remain stationary in phototropic positions, the tip of each arm 

 being turned towards the shade. When the former can find no shade 

 they end by assuming phototropic positions, but they do this more 

 slowly and less perfectly. 



Parthenogenesis of Sea-urchins. J — Yves Delage suggests that one 

 reason why Loeb's experiments do not agree with his may be found in 

 some constitutional difference between the Strow/ylocentrotus jnopuratus 

 of California and the Paracentrotus lividus of Europe. In Loeb's ex- 

 periments with the eggs of the California^ form, pure saccharine solu- 

 tions, in strong concentration, but without any reagent added, resulted 

 in abundant parthenogenetic ova ; in Delage's experiments with the eggs 

 of the Brittany form, it was always necessary to add some reagent, acid 

 or alkaline, or tannate of ammonia, but without exceeding the concentra- 

 tion corresponding to an isotonic solution. The sea-water does not 

 permit development except when the osmotic pressure of its salts has 

 been much diminished by the addition of distilled water, and when it has 

 been rendered isotonic by means of sugar. If Loeb had worked in 

 Brittany he would have found that hypertonic solutions (whether alka- 

 linised or not) and soluble fatty substances are ineffective, and he would 

 have found the tannate of ammonia method, or something equivalent. 



Littoral Holothurians of Indian Ocean.§— R. Koehler and C. Vaney 

 report on a collection of 51 species, of which 15 are new, 3 of Holothuria, 

 2 of Phyllophorus, 8 of Cucumaria, and 2 of Thyone. It may be noted 

 that Cucumaria inflexa has simple tentacles ; C. bacilliformis has a rod- 

 like body and a rigid carapace of calcareous plates ; the limits between 

 Thyone (with tube-feet not in regular rows) and Cucumaria, between 

 Pseudocucumis and Phyllophorus, are vague ; Holothuria glaberrima, 

 found in the Mergui Archipelago, has also been found on the east 



* Records Indian Museum, ii. pp. 11-19 (7 figs.). 



t C.R. Soc. Biol. Paris, lxiv. (1908) pp. 633-5 (3 figs.). 



% Comptes Rendus, cxlvi. (1908) pp. 262-5. 



§ An Account of the Littoral Holothurioidea collected by R.I.M.S.S. ' In- 

 vestigator.' Calcutta: printed by order of the Trustees of the Indian Museum, 

 (1908) 54 pp., 3 pis. 



