426 



it the above name, which is here, with some hesitation, adopted. 

 The younger shell, figured in Plate lxxxix, is certainly the same as 

 Chemnitz's Plate xlvii. fig. 474, 475, referred to by Lamarck as 

 S. spalhuliferus, but differs entirely from those wliich he has so 

 named in his own collection. 



22. Spondylus ducalis (pi. lxxxv. f. 16.), Chemn. t. 7. 

 pi. xlvii. f. 477, 478. 



S. testa ovali, griseo lineata, prope umbonem variegata, cardine 

 et auriculis magnis ; costis 9 ad 10, vix elevatis, albis; squamis 

 subarcuatis, palmatis, plerumque distantibus ; interstitiis striatis. 



Of an oval form, with broad auricules stripped with dark grey, 

 and rather variegated at the apex. There are nine or ten 

 ribs with short, white, palmated, slightly arched scales. In 

 many specimens, however, the scales are nearly obsolete. The 

 grey stripes between the rows of scales form a rather strongly 

 marked character, in this species, and distinguish it from S. 

 Lamarckii. 



Locality, " Indian Seas," Lamarck. Philippines, H. Cuming. 



23. Spondylus fragixis (pi. lxxxix. f. 57.), nobis. 



S. testa tenui, ovali, tenuissime striata , auriculis parvis ; squa- 

 mis erectis, tenuis, numerosis, palmatis, subdivisis, per series 6 

 principalibus (alternis minoribus), aculeatis dispositis ; interstitiis 

 imbricatis j colore palidissime fulvo, prope umbonem maculis fuscis 

 interruptim radiato, ad interstitias punctato, ad squamas roseo 

 tincto ; valva inferiori aculeata, inter spinas scabricula. 



Much thinner than the thinnest varieties of S. ducalis, and 

 having much smaller auricles. The scales are also much thinner 

 and more gracefully elongated than in that species. The inter- 

 stices are finely imbricated. The colour is arranged near the apex 

 in radiating rows of dark angular patches, which near the margin, 

 are subdivided into minute dots. Mr. Sowerby, sen., posesses two 

 specimens of this elegant shell, the locality of which is unknown. 



24. Spondylus vapians (pi. lxxxvi. f. 21, 22.), Sowerby, 

 Appendix to Catalogue of Polynesian shells collected by Mr. Sam. 

 Stuchbury, p. 1. Owen, Article on the ' Water-clam in Mag. of 

 Natural History, new series, 1838. Spondylus Delessertii, Chenu. 

 Illust. conch, pi. xii. Test, junior, S. obliquus, Chenu. Illust. 

 conch, p. 7. pi. xxiv. f. 5. 



