224 TUEBO. 



Section 13. Cookia. 



117. CooKiANUS, pi. vii. f. 72, Chemnitz 1540, 1554 

 (Trochus) — sulcatus, 31 arty n — Davisi, Hutton. — Testa tu- 

 mido-conoidea, imperforata, sordide fusca; anfractus 7, 

 rotundati, costis obliquis imbricato-squamosis, striis incre- 

 menti lamelliformibus dense oblique decussatis exsculpti ; 

 basis medio concava, versus marginem convexiuscula, dense 

 imbricato-lirata ; apertura oblique ovata ; columella tenuiter 

 late expansa, concava, fulvo tincta. Operculum ovale, extus 

 album, fusco tinctum, Isevigatum, costa latiuscula submar- 

 ginali munitum. — This species, from its form, has long- been 

 considered a Trochus. It is the only species of Lesson's 

 genus Cookia. Hutton's T. Davisi is a variety of this species 

 of a more pyramidal form than the type. 



Section 14. Lithopoma. 



118. TUBER, pi. xii.f. 148, Linnaeus (Trochus), Syst. Nat. 

 p. 1230. — Testa conico-turbinata, imperforata, albida, fusco 

 et viridi maculata et variegata, lineis fuscis obliquis hie illic 

 interruptis penicillata ; anfractus plus minusve angulati, 

 interdum oblique costati ; anfractus ultimus subventricosus, 

 plerumque nodoso biangulatus ; basis convexa, oblique leviter 

 striata, costis concentricis 4-5, fere obsoletis ; apertura 

 ovata. Operculum ovale, extus album, convexum, medio 

 arcuatim unicostatum ; costa prominente, granosa. — A shell 

 of stony substance, rather smooth, with the last whorl mostly 

 biangular, generally more or less noduled, sometimes obso- 

 letely ribbed at the upper part of the whorls, sometimes 

 smooth. — Hab. West Indies. 



Section 15. Pomaulax. 



119. UNDOSUS, pi. X. f. 120, Wood (Trochus), Index Test. 

 Supp. pi. V. f. 7^ — T. gigas, Anton. — Testa turbinato-conica, 

 imperforata, albida, epidermide fusca dense fibrosa induta ; 

 anfractus declives, superne concaviusculi, inferne leviter 

 concavi, oblique striati, costis brevibus obliquis, et nodulis 

 majusculis exsculpti, ad suturam carina undato-tuberculata 

 ornati. Anfr. ultimus infra medium conspicue undato- 

 carinatus; supra carinam leviter excavatus, infra planus 



