146 WORMS. TESTACEA. 36. Mya. 



114. Pb. striata. Somewhat conic, strongly reticulate on 

 the upper part, irregularly striate on the lower. 



Donovan's Shells t. 117. Chemn. Conch. 8. f. 102./. 864-866. 



Shell half an inch long, 3 quarters broad, white, the striae here 

 and there decussate, the part about the hinge f mooth, the lower-end 

 gaping : tooth long, slender, much curved. 



B. Bivalves. 

 36. MYA. 

 175 . M. Glycemeris. Oblong-oval, coarse, lamellar, with 

 transverse wrinkled striae, gaping at both ends, 

 obliquely truncate before and behind the beak : pri- 

 mary tooth of the hinge very thick. 



Donovan t. 143. Lister t. 414./. 258. 



Shell 5 inches long, 8 or 9 broad, grey or ochraceous, with an ir- 

 regular margin : beak nearly central, slightly indented both sides : 

 hinge with a lesser tooth and a feries of wrinkles. 



116. M. truncata. Suboval, truncate and much gaping at 

 the smaller end : tooth broad, thick, very obtuse, 

 projecting, erect. 



Br. Zool. t. 41./. 14. Donovan t. 92. Da. Cost. t. 16./. 1. 



Shell 2 inches and a half long, 3 and a half wide, covered with a 

 yellowish skin, white under the skin, marked with concentric 

 wrinkles. 



111. M. arenaria. Oval, rounded behind : tooth broad, 

 thick, very obtuse, projecting, erect, with a small 

 lateral-one. 



Donovan t. 85. Br. Zool. iv. t, 42. 



Shell o. inches and a half long, 3 wide, covered with a brown skm, 

 concentrically wrinkled: refembles the last, except in not being 

 truncate at the gaping end ; tooth with a projection near the bafe. 



118. M. margaritifera. Oblong, slightly kidney-shaped, 

 decorticated near the hinge, with a single tooth in 

 one valve locking into a forked one in the other. 



Donovan t. T\. Br. Zool. t. 43. Da Costa t. 15./. 3- 



Shell 2 inches long, 5 broad, a little contracted in the middle at 

 thf thinner end, thS'ck, covered with a black skin which b worn 

 off on the protuberant parts near the hinge, transverfely wrinkled, 

 pearly greenish within: teeth strong. 



119 M. Fictarum. Oval, in each valve a broad crenate 

 ' tooth, with 2 lateral laminae in one valve, and one id 

 the opposite locking into each other. 



Ticnovan t. 80. Brit. Zool. tab. 43* /• \7' ,. , .. t. 



T// nearW . inches long,. and 4 broad, dull green, nearly black 



at the "mailer end, concentrieally wrinkled, pearly wnh.n : tut 



18 0: e M t . h S. ren Oval.oblong, rounded at both ends: 



, 8 , e tLSrOvaf, 8 thin, brittle, saping, light rufous, 

 1 ^th the rudiment of a tooth in one valve projectmg 



inwards. 



