MAZATLAN BIVALVES 37 



process of Cumingia, but tlie ligament is scarcely apparent. 



Long. -06, lat. -Qil, alt. "Oi. 



Ba6.— Mazatlan : from Spondylns washings ; L'pool Col. 



Tablet 120 contains aU that was foimd ; vi^. 1 perfect valve 

 with a portion of the other. 



58. Tellixa lamellata, «. s. 



T. t. "Tellinm lirce" simili, sed magis (Bquilaterali, et carina 

 umbomim carente : lamellis acutissimis, irregulariter distanti- 

 bus ; umbonibus valde prominentibiis. 



A beautiful little shell, verj^ flat, thin, white, transparent ; 

 cardinal and lateral teeth moderately strong ; spaces between 

 the lameUse smooth ; -outline oval, very regular except where 

 the umbos project ; flexure wanting. It might have been the 

 young of T. lira, but for the entire absence of the stout umbonal 

 ridge of that species. Long. "1, lat. '13, alt. '03. 

 Sab. — Mazatlan ; nestling on back of Chamse and Spondylus 



Lamarcku, extremely rare ; L'pool Col . 



Tablet 121 contains 1 pair and 2 opposite valves. 



59. Tellina ?? puELLA, C. B. Ad. 



C. B. Ad. Pan Shells, p. 283, no. 468. 



Tablet 122 contains an open pair and a valve wliieh may 

 belong to this species. I think however that the valve is dis- 

 tinct, and displays certain symptoms of Semele, of which I 

 have not seen the very young shell, and am therefore ignorant 

 of its variation in growth. An unfortunate cough made away 

 with the opposite valve, which however had previously adhered 

 by an external ligament. WTiether there be an internal liga- 

 ment as well, repeated microscopic examination has as yet failed 

 to determine. Long. "075, laf. '095, alt. "035. 



60. Tellina ?? delicatula, Des/t. 



Proc. Zool. Soc. 1854, p. 363. 



Tablet 123 contains a fragment which may possibly be the 

 young of this exquisitely beautiful species. Mr. Cuming's 

 imique specimen dispLays, in addition to the features recorded 

 in Desh.'s description, a pretty general penciling of a dark 

 Sept. 1855. e 



