250 TESTACEOUS MOLLUSCA. 
*M. Eputis. Lin. Sys. 1157.—Fab. Faun. Gr.—D. p. 309.— 
Lam. 29.—Turt. Dic. p. 109.—Dor. Cat. t. 12. f. 5.-——Da. Cost. t. 
15. f. 5, (left-hand figure)—Ch. f. 750.—Knorr. 4.1.15. f. L— 
Et. 218. f. 2.—Macg. Ab. p. 234.—W.t. 12. f. 22. (not good)— 
Don. t. 128. f. 1. Oblong, convex, nearly smooth, dark blue 
(sometimes with paler rays) hinge margin short, convex, forming 
a rounded off but evident angle with the anterior, which is but little 
arcuated, and subparallei to the posterior, the latter being nearly 
straight and slightly tumid towards the rather acute beaks; the 
base (or anterior ventral edge very obtuse): hinge with a few 
denticles. 
Variety? M. Petiucipus. Pen. 4. t. 63. f. 73. (tolerable)— 
D. p. 810.—Don. t. 81.— Ch, f. 755. (tolerable)—W, t.12.f. 22. 
—Mont. p.166. Tawny, with blue rays, pellucid, the dorsal angle 
more distinct. 
Var. M.Incurvatus. Pen. 4. t. 64. f. 74.—Lam. 33.—W. t. 
12. f.48.—Lin. Tr. 8. t. 3. f.7. So distorted that the back is 
greatly arched, the posterior edge strongly incurved and the base 
dilated. 2. The common mussel. N. W. Europe. ! 
M. Hesperianus. Lam. 32.—lList. t. 362. f. 202?—Payr. 
Cat. p. 68. t. 2. f. 5. Narrow, oblong, the sides nearly equal, 
rounded at the margin, dark blue with the beaks white, acute and 
somewhat curved: hinge with the teeth obsolete. 12.—/Spain. 
I believe this is only a variety of Edulis. 
M. Conrvusus. Ch. f. 753.—M. Linsatus Gmel. 3359.—W. t. 
12. f. 27.—D. p. 212.—E. t. 218. f. 4. Oblong-triangular, 
dilating from the apex, of a dirty yellowish green with oblique 
impressed lineoles decussating the transverse striae: pearly within 
and the hinge with two teeth. +.—Adriatic near Venice. 
M. Lacunatus. Lam. 35. Incurved, dilated at the opposite 
extremity to the beaks which are acute: the middle of the posterior 
side indented with ahollow. 2,.—Australia. 
M. Minimus Poli. 2. t. 32. f. 1.—Desh. in Lam. 7. p. 49.— 
Payr. p. 69.—Phil. p. 73. Small, elongated, narrow, arched in 
the middle, gibbous on the back, obliquely subcarinated, brown or 
violet blue, and finely striated concentrically; umbones minute 
and not quite terminal. Mediterranean. According to M. Chant- 
eraue is a diseased Hdulis. 
M. Potymorruvus Pallas.—Gmel. 3363.—W. 8. t. 2. f. 6.— 
Reeve. t. 102. f. 4.—Sow. G. f. 4.—Dreissena. P. Gray. Tut. 
p. 301.—(Ch. f. 2028.) Triangular, inflated, smooth, carinated : the 
posterior face flat, concave, with a cleft for the byssus in the centre; 
yellowish olive with transverse ziezac stripes : within white and not 

''M. Deshayes states that the M. Anpreviarus. and Rrresus 
(Del. t. 14. f. 1.) Lam. 30, 31. are varieties of this species. 
