448 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Role of Mucus in Corals.* — J. E. Duerden finds that the outer surface 

 of coral polyps is covered with a thin mucus layer, which entangles 

 objects falling on it. When first extruded it is thin and watery, 

 becoming firmer later. From time to time it gets broken up into 

 shreds, which are wafted off the disk by the exhalant currents from the 

 stomodaeum, carrying with it adherent foreign particles. Nutritive 

 substances and extractives placed upon the polyp increase the amount of 

 mucus, and also result in an opening of the mouth and the institution of 

 an inhalant stomodgeal current by reversing the dominant outward beat 

 of the stoinodeeal cilia. At the same time, the mucus is drawn down 

 along with its entangled nutritive or non-nutritive particles into the 

 stomodgeum. Ingestion in coral polyps is thus purely mechanical, de- 

 pending upon whatever substances are capable of producing an inward 

 beat of the cilia, the opening of the mouth, and the exudation of mucus. 

 An inhalant current being established, objects are carried into the polypal 

 cavity without regard to their nutritive value, and independently of any 

 peristaltic motions on the part of the stomodaeum. 



Japanese Alcyonarians.f — W. Kukentkal gives diagnoses of a 

 number of new Japanese species : — Anihelia japonica, Clavularia (three 

 sp.), Nidalia (five sp.), Alcyonium gracillimnm, Dendronephthya (six sp.), 

 Gersemia marenzelleri, Eunephthya japonica, E. spicidosa, Siphonogorgia 

 dofteini, and S. splendens. 



New Species of Semper's Larva from the Galapagos Islands.^ — 

 Harold Heath describes under the title Zo anihelia galapagonensis a new 

 species of Semper's larva, but is unable to offer any suggestion as to its 

 relationships. 



Porifera. 



Bengal Variety of Spongilla lacustris from Brackish Water.§ — 

 Nelson Annandale describes Spongilla lacustris var. bengalensis n. from 

 brackish water at Port Canning in Lower Bengal. There is a total 

 absence of branches. The spicules most nearly resembled those of 

 Pott's variety montana. The gemmules were very distinctly of two 

 sizes, scattered indiscriminately, not grouped, and without large air-cells. 

 The green colour was due to a multicellular alga. Enormous numbers 

 of gemmules formed a scum on the surface of the pools, and some 

 seemed to have been carried to a distance by the wind. 



Protozoa. 



Atlanticellidse.lJ — A. Borgert establishes a new family of Radio- 

 larians (Tripylea) which he calls Atlanticellidge. The diagnosis reads : — 

 " Tripylea, with a free vesicular central capsule not inclosed in skeleton ; 

 the skeleton is absent, or forms an oval appendage of the central capsule ; 



* Quart. Journ. Micr. Sci., No. 196 (pp. 591-614). 



+ Zool. Anzeig., xxx. (1906) pp. 280-9. 



% Tom. cit., pp. 171-5 (4 figs.). 



§ Journ. and Proc. Asiatic Soc. Bengal, ii. (1906) pp. 55-8 (1 fig.). 



|| Ergebn. Plankton Exped., iii. (1906) pp. 117-28. 



