423 



in which the interstices are more distinctly striated than in those 

 which Mr. Broderip has named S.princeps. By the rule of pri- 

 ority, both names, together with Lamarck's S. crassisquama, 

 given on the authority of specimens so named in Lamarck's col- 

 lection, must give place to that which we have adopted, on an 

 examination of the figures in Chemnitz. Mr. Cuming's speci- 

 mens are from the Isle of Plata, West Columbia, and from the 

 Gulf of Tehuan. Mr. Sowerby posesses a small shell, which ap- 

 pears to be a variety of this, but which may be distinct, from China. 



14. Spondylus leucacantha (pi. lxxxvii. f. 35, 36.), Brod. 

 Proc. Zool. Soc, 1833, p. 5. 



S. testa solida, ventricosa, ovali ; costis 6 principalibus, squarnis 

 elongatis subarcuatis, lsevibus, angustis, subtus concavis, ad ter- 

 minum subtruncatis ; interstitiis minutissime imbricatim striatis, 

 costis vix elevatis, tribus (media maxima) aculeatis, regularibus, 

 subarcuatis, ornatis ; colore croceo vel rubro ; squarnis albis. 



Tliis elegant species is named from the beautifully white scales 

 standing out from an uniform ground of bright orange or scarlet. 

 The shell is solid, with six principal ribs, armed with strong, even, 

 and rather lengthened scales, which are slightly flattened and de- 

 pressed, but not spread at the ends. Between each rib there are 

 three rows of scales, some of which are pointed at the ends. 



Collected by Mr. Cuming at the Island of Plata. 



15. Spondylus unicolor (pi. lxxxv. f. 19.), Sowerby, Proc. 

 Zool. Soc. May, 1847. 



S. testa solida, oblique ovab, rubro violascente ; costis 6 prin- 

 cipalibus, squarnis crassis, arcuatis, subtus concavis, paululum 

 palmatis, prope marginem numerosis ; costis interstitialibus, spinis 

 crassis, brevibus, armatis ; inter costas sulcis nonnullis. 



Solid, obliquely oval, of an uniform purplish-red colour, which 

 is shown in the interior by a strongly defined, deep red margin 

 round a white centre. The five or six most prominent ribs are 

 ornamented by strong, arched, hollow spathulse, which are slightly 

 depressed and palmated at the end. The intermediate ribs are 

 studded with short thick spines near tne margin. Between some 

 of the ribs there is occasionally a deep groove ; in the thickness 

 and arrangement of the scales and ribs, and in the solidity of the 

 shell, it resembles S. pidorum, from which it differs principally in 

 the more tumid and obliquely oval form of the fully developed 

 specimens. After figuring M. Gruner's specimen, we have met 



