ZOOLOGY OF FERNANDO NORONHA. 
493 
29. Hipponyx Gray anus, var. 
Hipponyx Grayanus, Menke, Carpenter, Proc. Zool. Soc. 1856, p. 4; 
Crosse, Journ. de Conch. 1862, vol. x. p. 23. 
The distribution of this species appears to be very extensive. 
Carpenter quotes it from Galapagos, Sandwich Islands, Panama, 
S.W. Mexico, Mazatlan, and St. Vincent (W. Africa). Some 
specimens in the British Museum from St. Helena, wrongly 
named H. radiatus, Quoy & Gaimard, by Jeffreys*, and two 
specimens from Fernando Noronha agree in all respects with this 
species except in the more excentric position of the apex, which 
gives them a more capuliform appearance. 
30. Nerita ascensionis, G-melin. 
In his monograph of Nerita in the Conchylien-Cabinet, Dr. 
von Martens mentions only the island of Ascension and Guinea 
as localities for this species. I had previously noted f the fact of 
its occurrence at the island of Trinidad off the Brazilian coast, 
and now I record its presence at Fernando Noronha, where it was 
also obtained by the ‘ Challenger ’ Expedition. 
31. Turbo (Calcar) Olfersi, Troschel. 
Ti’ochus Olfersi, Troschel, Philippi, Conch.-Cah. ed. 2, p. 126, pi. 22. 
f. 1. 
Calcar Olfersi, Fischer in Kiener’s Coq. Viv. p. 18, pi. 77 ■ f. 1. 
Troclius digitatus, Reeve ( non Deshayes ), Conch. Icon. pi. 5. f. 24 ; 
Sowerby, Thes. vol. v. pi. 504. fig. 135. 
Had. Brazil ( Philippi <Sf Fischer). 
The localities quoted by Beeve and Sowerby, namely Central 
America and Panama, will doubtless prove incorrect. 
Failing to recognize this species as T. Olfersi, Sowerby has 
placed that name among the synonymy of T. imbricatus , which, 
however, is a perfectly distinct shell. T. digitatus of Deshayes, 
as pointed out by Philippi, Fischer, and Carpenter, is identical 
with the common T. unguis , Wood, of the Californian coast. 
32. Trochus (Eutrochus) jujubinus, G-melin. 
Hal. West Indies ( Philippi Sf Fischer ). 
The two specimens from Fernando Noronha are more widely 
* Ann. & Mag. Nat Hist. 1872, vol. ix. p. 264. 
t Ibid. 1881, vol. viii. p. 431. 
