36 SYEIAN MOLLUSCAN FOSSILS. 



On applying to Conrad's figure a recent 3£elo j^tMopica of corresponding size, 

 such coincidence of outlines appears as convinces the observer that the two 

 are genericallj' equivalent. 



Fossil species of Mch are rare, but are found in the Cretaceous and 

 Tertiary formations. Stoliczka describes a single species, 31. pi/rij'onnis 

 (Cretaceous Gastropoda of Southern India, p. 83, PI. vi, fig. 9) from India. 



Lartet (Expl. Gcol. de la Mer Morte, p. 115), under the heading Strombus 

 pcrvdns, speaks as follows : " Nous avons trouve an waddy Heidan un moule 

 de Gasteropode qui se rapproche de cette forme et ressemble ainsi au Ptcro- 

 ccra inornalid' Our specimen and that figured by Conrad, on comparison, 

 will be found vi'i-ij unlike P. imrnaia d'Orb. (Paleont. Frani;., Terr. Cret., II, 

 PI. ccxiv). Coll. Merrill. 



Locality and Position. — Beirut district ; from a yellow marl, probably 

 Turonian. 



Cerithium gracilens, sp. nov. 



Testa elongata, turrita, spirw ane/idus 14°-16°, sutitra' 87°: anfrcictus multi, 

 complamdi, paulum excavaii, sidiira 2^^'ofunda sejundi, terms .serielus tubercidorwn 

 ormdl tuber cidis in serie mcdiana ceteris nndto minorit)ns : basis anfractus 

 idlinn subconvexa, moderate producta, spiraliter serie una tuberculata ; aper- 

 turu rpiadrangidaris, aidice cannii angitsto tenninans. 



An elongated turreted shell composed of numerous flattened volu- 

 tions, which increase very gradually in length and width. Each of 

 the whorls is ornamented with two rows of rounded and close-set 

 tubercles, adjacent to the suture, which are so prominent as to give 

 to the volutions the appearance of being somewhat excavated. Midway 

 between these rows is a third, made up of much smaller tubercles, less prom- 

 inent and distinct. 



Nineteen specimens, none entire, but the greater number retaining the 

 test. 



It may liave been such specimens as these, found at Abeih. which Fraas 

 considered to be C. trimonile Michelin* (Aus dem Orient, II. Theil, p. 70). 

 That species is very extensively distributed, for besides being known in the 

 Gault of France, it has been recognized by Stoliczka in Southern India. On 

 comparison with Michelin's, d'Orbigny's, and Stoliczka's figures of C. trimonile, 



* Mem. Soc. Geol., Ill, p. 100, PI. xii, fig. 5, 1838. 



