ZOOLOGY AND BOTANY, MIGltOSCOPY, ETC. 177 



Certain luminous Ostracods reacted by emitting a luminous secretion in 

 response to a light cast on the bottom from an acetylene bicycle lamp. 

 Areas of half-an-acre would show a glow. Cirratulids seemed to attract 

 one another by a brilliant glow, and they came directly towards a small 

 incandescent globe, at the same time becoming brilliantly luminous. A 

 Syllid with unusually well-developed eyes, probably Odontosyllis pachij- 

 donta Verrill, behaved in the same way. The author's view appears to 

 be that the luminescent reaction helps to bring the sexes together. 



Galls made by Animals.* — In the first part of a treatise on Zoo- 

 cecidia, edited by E. H. Riibsaamen, there are three contributions. Fr. 

 Thomas has compiled a very exhaustive bibliography. A. Nalepa gives 

 a systematic account of the gall-mites of the family Eriophyidte, the 

 genus Eriophyes alone including no fewer than 144 species. E. Kiister 

 supplies an extremely interesting general introduction to the study of 

 galls. He discusses the definition of galls, their classification, the 

 animals that cause galls, the plants that bear them, the position of galls 

 on the plant, the morphology of galls, the structure and development of 

 galls, the biology of galls, their astiology and palteontological record, 

 their uses and injurious effects — a very valuable contribution to a 

 fascinating subject. 



INVERTEBRATA. 



MoUusca. 



7- Gastropoda. 



Warning Coloration in Chromodoris.t — Cyril Crossland calls atten- 

 tion to the almost universal occurrence of colour in the family of Chro- 

 modorids, and to their habit of crawling about in the open instead of 

 skulking under stones or in crannies. It is probable on general grounds 

 that the bright colours have some protective value. Distastefulness 

 was proved by trying to feed numerous fishes with Chromodorids. 

 They would not swallow them, though they would swallow pieces of 

 Margaritifera and Batistes that had been in formalin ! Some would 

 dash up to a Chromodoris thrown into the water, and then turn away 

 after touching it. Others took the Chromodorids into their mouths 

 and at once dropped them undamaged. There is no doubt that these 

 conspicuously coloured Nudibranchs are naturally protected. 



Red Sea Chromodorids. J — Charles Eliot gives some account of 

 Chromodoris reticulata Pease, C. tinctoria Riippell and Leuckart, G. ino- 

 pinata(?) Bergh, collected and studied by Cyril Crossland. There is 

 considerable variety, not only in the colour but in the details of the 

 buccal parts. In what appears to be the same species, the denticulation 

 of the teeth and the shape of the elements in the labial armature may 

 vary, and thickenings of the rhachis, amounting to rudimentary central 

 teeth, may be present or absent. 



* Zoologica, xxiv. (1911) pp. 1-293 (6 pis.). 



+ Proc. Zool. See. (1911) pp. 1062-6. 



X Proc. Zool. Soc. (1911) pp. 1068-72 (1 pi.). 



