-_ 
MAZATLAN BIVALVES 37 
rocess of Cumingia, but the ligament is scarcely apparent. 
Long. °06, lat.°07, alt. OA. 
Hab.—Mazatlan: from Spondylus washings ; Z’poo/ Col. 
Tablet 120 contains all that was found; viz. 1 perfect valve 
with a portion of the other. 
58. TELLINA LAMELLATA, 2. S. 
T.t. “ Telline lire” simili, sed magis equilaterali, et carind 
umbonum carente : lamellis acutissinis, irregulariter distanti- 
bus ; umbonibus valde prominentibus. 
A_ beautiful little shell, very flat, thin, white, transparent ; 
cardinal and lateral teeth moderately strong; spaces between 
the lamelle 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. 
Hab.—Mazatlan ; nestling on back of Chama and Spondylus 
Lamarckii, extremely rare; ZL’ pool Col. 
Tablet 121 contains 1 pair and 2 opposite valves. 
59: TeLiina ?P puELLA, C. B. Ad. 
C. B. Ad. Pan Sheils, p. 283, no. 468. 
Tablet 122 contains an open pair and a valve which 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 therefere ignorant 
of its variation in growth. An unfortunate cough made away 
with the opposite valve, which however had previously adhered 
by an external ligament. Whether there be an internal liga- 
ment as well, repeated microscopic examination has as yet failed 
to determine. Long. °075, lat. °095, alt. '035. 
60. TrLiina ?? peLIcaTtuLa, Desh. 
_ 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 
unique specimen displays, in addition to the features recorded 
in Desh.’s description, a pretty general penciling of a dark 
Sept. 1855. € 
