415 



scribed the Ceecum trachea under the name Odontina, in the Mem. 

 Soc. Nat. Moscou, vol. iii. p. .'ilO, pi. 27. f. 5. This rare work had 

 not been seen by Philippi ; nor have I been able to meet with a copy 

 containing the above citation. 



In the celebrated Moll. Sic. Utr. vol. i. p. 102, 1836, Philippi 

 redescrihes the Ceecum trachea as Odontidmm rugmlotim, and Magna 

 his new genus a place among the Pteropods. This place ifl retained 

 in vol. ii. p. 73, where he cites the English synonyms, and quotes 

 Cantraine, who had previously figured the shell as a Creseis. 



In 1842, Mr. Searles "Wood catalogued four fossil species from 

 the Coralline Crag, in the Ann. and Mag. Nat. Hist., for the first 

 time directing attention to the shape of the plug as a guide in spe- 

 cific determination. In the Monogr. Crag Moll. (vol. i. of the im- 

 portant works published by the Pakeontological Society), 1H48, the 

 species are further illustrated and figured, being arranged b etween 

 J'ermetus and Litorina. The types were presented to the British 

 Museum, but without names. 



Previously to the publication of Philippi's views, W. Clark, Esq., 

 in 1834, had discovered the animal of Ceecum trachea, and ascer- 

 tained its true relationships. It was not, however, till lsij thai 

 he published his observations in the Ann. Nat. Hist. ser. 2. vol. iv. 

 p. 180. In his Moll. Test. Mar. Brit., 1855, pp. 322-331, he mi- 

 nutely describes the animals of the two British species, resigning his 

 MS. designation of Dentuliopsis, and inserting Fleming's genus, with 

 Turrit I'll a, in the family Vermetidee*. 



In 1851, the British species were carefully described and the 

 animal of C. trachea figured in Forbes & Hani. Brit. Moll. vol. iii. 

 pp. 176-183. Prof. Forbes placed the genus in Turritellidee, and 

 confirmed many of the observations of Mr. Clark. Mr. Ilanley ex- 

 perienced difficulty in assigning Brown's species, saying that " the 

 genus Ceecum has not been studied with that due attention to its 

 foreign members which alone entitles us to pronounce upon what 

 are the permanent characters by which its species are determinable." 

 This want it is the object of the present paper to aid in supplying. 



In the same year (Oct. 15th, 1851), Mr. Stimpson presented a 

 Monograph of the species found in the United States, to the Boat. 

 Nat. Hist. Soc. It is published in their ' Proceedings,' and contains 

 descriptions of the shells of two species from Florida, and one from 

 New England. In his 'Shells of New England ' is given n figure 

 of C. pulchellum, and an account of its animal (p. 36), agreeing in 

 the main with Clark's observations on C. trachea. 



In 1X52, the late lamented Prof. C. B. Adams published his Mo- 

 nograph of the Shells of Panama in the ' Annals of the Lyceum of 

 Nat. Hist. New York.' At pp. 160-163, 310, 311, eight supposed 



* I have to record my greatest obligations to Mr. Clark for the k.ind»rs> with 

 which he has supplied me with the records of his laborious resear ches, and fa. 

 vmirrd me with perfectly fresh British ipecimens. A few ><( bis 

 p. p.,thsl iSkenea rot a "Ceecum trachea, jun. ; thai the yoons; Qses sis Isad | thai 

 the operculum of Brochma glabra is analogous tothsl H fl M f —rt s hare art besa 

 confirmed. 



