48 Mr. C. J. Galian on neiv Species of Longicornia 



The contracted and opaque condition in spirit prevents a 

 satisfactory examination of the soft parts, but, as indicated in 

 the outline (Plate VIII. fig. 3), three regions occur anteriorly. 

 These probably correspond to the head, the fin, and the pos- 

 terior division of the foot. 



The occurrence apparently of an example of a group of 

 mollusks formerly unknown in British seas is noteworthy. 

 Hitherto they have been considered characteristic of the 

 pelagic fauna of the more genial oceans, such as the Medi- 

 terranean and the warmer parts of the Atlantic and Pacific. 

 All recent investigations however, tend to enlarge the area of 

 truly pelagic types, and to raise the question whether tem- 

 perature alone is the cause of the appearance and disappear- 

 ance of such forms in our seas. It is true temperature 

 appears to have a marked effect on the vertical distribution 

 of certain types and the pelagic ova of fishes ; but in the case 

 under consideration the influence of currents is probably of 

 greater importance. 



EXPLANATION OF PLATE VIII. 



Fig. 1. Abnormal Thaumantias, devoid of manubrium and mouth. The 

 reproductive bands meet in the centre. About natural size. 



Fig. 2. Mouthless example of Tima Bairdii, the central region being 

 imperforate. 



Fig. 3. Lateral view of Atlanta from St. Andrews, x 31. 



Fig. 4. View of the same on edge. The opaque central region is the mass 

 formed by the contracted body of the mollusk. Similarly en- 

 larged. 



VII. — Descriptions of new Species of Longicornia from India 

 and Ceylon. By Charles J. Gahan, M.A., Assistant, 

 Zoological Department, British Museum. 



[Plate VII.] 



The present paper is in great part the result of my work upon 

 a small collection of Longicornia made by G. F. Hampson, 

 Esq., in the Nilghiri Hills, S. India, and kindly placed by 

 that gentleman at the disposal of the British Museum. In 

 the descriptions, however, I have not confined myself to 

 species from the Nilghiris, but have included also species 

 from other parts of India and Ceylon which had already 

 existed unnamed in the British Museum collection. 



Prionidae. 



Iihaphipodus subopacus } n. sp. 

 Capite prothoraceque nigro-fuscis : elytris fusco-brunneis, subopacis, 





