429 



Indies, and three from the Eastern Seas, as well as one pseudo- 

 British specimen from Mr. Alder's cabinet*. Thej are all rery 

 constant and regular in the arrangement of the rings, never present- 

 ing so many as are recorded tor ('. Floridantun, and farther differing 



in the contraction of the mouth. More exact information abool tin- 

 Florida species may, however, prove them identical. 



23. Cecum gracile, n. s. 



C. (Anellum) t.valde tereti, parva, anntdu circiter cut. tubdistan- 

 tibus, eubacutia ornata ; apertura hand contractu, haud decHvi, 



annul o valido cincta ; septo 1 , margin* laterali subpla- 



nato : eperculo '. . . . 

 Long. -09, lat. -012— -017. 

 Hah. Japan (Stitnpsori). Mus. Smithsonian. 



Dr. Gould, to whom is entrusted the duty of describing the shells 

 of the U.S. Japanese Exploring Expedition, has kindly allowed me 

 to include the C'ceca brought back by Mr. Stimpson in the present 

 Monograph. They consist of but two specimens. One is a young 

 shell, with the plug broken off, closely resembling 0. elongatvm, \ ar. 

 semilceve, from Mazatlan. The other is the shell here described, 

 which, though dead and worn at the plug, is adult, and clearly distinct 

 from any other recorded species. It is much more slender even than 

 C. elegant issimmn, with the rings closer and not so sharp. 



24. Cecum elegantissimum, Cpr. 



C. (Anellum) t. diaphana, vitrea, nitida, alba, arcuata, tereti, 

 subelongata ; apertura parum declivi, parum contractu ; t.Jun. 

 Ift-vi ; t. tn/olescente et adult a liris concentricis distantibus 

 (xiv.— xviii.) acutis cincta ; interstitiis elongatis, elegantiwisne 

 rirruatis ; septo subniucronuto, subunguluto ; apire obtlMO, 

 parvo, haud valde prominente ; margine laterali concavo .■ 

 operculo ? . . . 

 Test. jun. long. -042, lat. 006— -013. 

 Test, adult, long. -1, lat. 014—023. 



Hab. Teneriffe, in gravel sand, .iO fins. ( R. M* Andrew). Mas. 

 Brit. &c. 



= Ceecum trachea, M'Andr. Geogr. Distr.Test., Liverpool, 1 s ."> I . 

 B.M. List Canary Shells, p. 29 (non Mont, et auct.). 



C. elegantieeimum, Cpr. in M'Andr. Rep. Moll. X. B. At!., Brit. 

 Assoc. 18o6, p. N9. 



More than 300 specimens of this exquisitely beautiful specie* irere 

 dredged by H. M' Andrew, Esq., in company with O. vitreun and 

 0. polUcare. It differs from O. undatum in it- glosai texture, 



slender form, and very distant rings: also in the plug, which i> in- 

 termediate between the mucronate and ongulate forms. The j 

 shell i> quite smooth ; and as soon as the rim.-- commence, they 

 are distant as in the adult. 



* Sec Note in llrit. Moll. W>L iii. p. 180. The otlier Speci men "" the »irar 

 earH was Meiocem cornucopia, slto from the W. tn 



