500 



MR. H. ]Sr. RIDLEY OIT THE 



54. Spondylus, sp. 



A few odd valves picked up on the shores are too much worn 

 to be identified with certainty. About a dozen forms have been 

 described as West-Indian ; and doubtless it is one or more of 

 these species which occur at Fernando Noronha. 



II. TEREESTRIAL SPECIES. 



1. Helix (Ophiogyra ?) QuiNQUELiRATA. (Pl.XXX. figs.7-7c?.) 

 Testa discoidea, supra leviter convexa, inferne anguste umbi- 



licata, tenuis, viridi-flavescens, nitida ; anfractus 7, lente accres- 

 centes, convexi, incrementi lineis striati, supra peripheriam in- 

 distincte concavus, antice hand descendens, intus plicis tribus 

 insequalibus perlucentibus munitus, lamellisque duobus validis 

 parietalibus instructus ; apertura semilunata, parva; peristoma 

 teuue, hand expansum. 



Diam. maj. 6 millim., min. 5^, alt. 3. 



Hal. Eound, both living and dead, at the north end of the 

 island, also on Platform Island. 



H. entodonta, Pfeiffer, from Ecuador, is an allied form; but 

 has a flatter spine, more open umbilicus, and no parietal lirse. 



2. BrLiMrs (Tomigerus) Kamagei, sp. n. (Plate XXX. fig. 8.) 

 Testa subovata, rimata, solida, fnsca, zonis angustis albis trans- 



versis (in anfr. ultimo quatuor) cincta ; anfractus 5, convexiusculi, 

 lineis incrementi subrugosis, striisque tenuissimis spiralibus 

 sculpti, ultimus magnus, antice descendens, post labrum con- 

 tractus, scrobiculatus ; apertura irregularis, longitudinis totius | 

 paulo superans, dentibus quatuor ina^qualibus (duobus parvis in 

 jmriete aperturali, uno magno compresso in margine dextro, uno 

 tuberculiformi valido in margine columellari) niunita ; peristoma 

 album, valde incrassatum, leviter reflexum, marginibus callo craso 

 junctis. 



Longit. 23^ millim., diam. 16. 



The above measurements show that considerable diflTerence 

 exists in the size of specimens ; and it is a curious fact that the 

 smallest example, obtained from a native, is the only one which 

 appears in fairly fresh condition. All the rest were found by 

 Mr. Kamage imbedded in sandy mud on a raised reef at Tobacco 

 Point, and have a semi-fossilized appearance. 



The only forms at all approaching that now described are the 



