419 



3. Spondylus aculeatus (pi. lxxxv. f. 11, 13.), Chemn. t. 44. 

 f. 460. S. dentatus, Chemn. pi. 25. f. 1. pi. 27. f. 2. 



S. testa ovali, purpurea vel fusca; costis 10 ad 11, spinis bre- 

 vibus numerosis, aculeatis, erectiusculis, albis ; interstitiis minute 

 spinosis. 



Of an oval form, with ten or twelve rows of white, short, rather 

 erect, numerous thick spines, upon a purple or brown ground, 

 covered with very fine spines. 



From the Mauritius. 



4. Spondylus Petroselinum (pi. lxxxiv. f. 6, 7, 8, 9, 10. 

 pi. lxxxviii. f. 49.), Chemn. vol. vii. t. 46. f. 472, 473. S. costatus, 

 Lam., Knorr. vergn. vol. i. t. 9. f. a. S. multilamellatus, Lam. ? 



S. testa ovali, lineatim purpurea, vel fusca, prope umbones 

 variegata; costis 6 validis, albis; squamis erectiusculis, arcuatis, 

 pbcato-palmatis ; interstitiis costis duobus vel tribus validis, plus 

 minusve divisis, nonnunquam scabriusculis. 



Figures 6, 8, and 10 probably represent S. costatus of 

 Lamarck. Fig. 9 is from a shell exactly resembling S. Petro- 

 silium, as represented by fig. 472, 473 of Chemnitz. From the 

 latter, in which the groves between the intermediate ribs are partly 

 filled up by laminae, and the palmated scales are nearly obsolete, 

 to the former, in which the ribs and spatula? are fully developed, 

 we possess specimens presenting an unbroken series of gradations, 

 rendering it impossible to separate them. Lamarck refers to the 

 same figures in Chemnitz (472, 473), first, for S. multilamellatus, 

 his description of which does not agree with them, and afterwards 

 for his S. longispina, with which they agree still less. The orange 

 variety is represented by the favour of Mr. Norris, from whom we 

 also received (when too late) a much finer specimen of the typical 

 variety than our figure (6) represents. 



Fig. 6 is from the Mauritius. Mr. Cuming collected var. f. 7 

 at the Isle of Ticao, Philippines. 



5. Spondylus croceus (pi. lxxxvii. f. 31.), Chemn. vol. vii. 

 t, 45. f. 163. 



S. testa ovali, crocea, costis quinque, spinis distantibus crassius- 

 culis ; interstitiis irregulariter costatis. 



This species has five or six ribs, with a few thick spines on each. 



