161 WORMS. TESTACEA. 48. Mytilus. 



SOS. M, ungulatus. Oblong-oval, smooth, incurved and' 

 much pointed at the beak : hinge terminal, 2 

 toothed. 



Donovan t. 123.7.. 2. c/ ^ ? - Conch. 8. t. 85.7. 756. 



Shell about 4 inches long, and 2 broad, bluish-black with a mix- 

 ture of green, much pointed and incurved at the beak, rounded be- 

 low: hinge with 2*6 teeth besides numerous crenatures on the 

 groove. 



309. M. Modiolus. Oblong, wrinkled, very obtuse at the 

 beak, wiih a gibbosity each side below it. 



r. Zool.t. 66 f. 77. Donov. t. 23. Da Cost. t. 15.7. 5. 



Shell 4 o; 5 inches long, 2 or 3 broad, covered with a purplish* 

 black skin, perlaceous within, .a little angular on one side, much 

 rounded at the beaks which are rather lateral. 



310. M. umbilicatus. Oblong, contracted into a deep 

 ragged cavity opposite the hinge r forming a deep 

 Hollow when the valves are closed. 



JSr. Zool. tab. '6$. f. 76. Donovan tab, 40. 



Shell about 2 inches long, thick, rounded at the beak, blackish, 

 contracted on one side into a deep rugged hollow under the 

 beak. 



311. M. rugosus. Rhombic-oval, rugged, brittle, anti- 

 qua'ed,-.obtuse at both ends. 



Br. Zool. tab. 63. f. 72. Donovan tab. 141. 



Shell about an inch and a quarter broad, half as much long, dirty 

 yellow generally covered with a yellowish skin, often gaping and 

 truncate at one end : beak fin all,. near the thicker and rounded end. 



312. M. prcecisus. Oblong, wrinkled*, one valve larger, 

 abruptly truncate at the end near the beak. 



Montague P.rit. Shells, p. 165. tab. 4.7^.- 



S/ze//refembling ; the last, except that it is fquare at the end near 

 the hinge, and one valve is rather larger and receives the other: 

 beak large, prominent ; hinge rugged, inflected, with a hollow under 

 the margin. 



313. M. Grata Galli. Affixed, spinous, compressedj 

 undnlately plaited on the margin; both lips rough. 



Ear but tab. i\.f. i. 2. Montague p< 166. 



Shell 2 inches and a half wide, varying in shape, ferruginous or 

 dull purple, deeply. plaited on the margin, affixed by the opposite 

 end, striate with raifed dots, glabrous and horn-colour within, 

 marked with a feries of raifed dots near the margin, armed exter- 

 nally with compressed fpines which are concave within: liinge 

 quite simple, linear, toothless. 



3 {4. M. discors. Oblong-oval, very convex, produced and 

 narrower at the anterior end, striate longitudinally 

 on both sides and transversely in the middle. 



Donovan tab. 25. Linn. Trans, viii. p.m. t. 3.f. 8. 



Shell s^n inch and a half wide, 4 lines long, brown, femitranfpat- 

 rent, strongly striate, longitudinally at the sides and very faintly 

 tranfvetfely in the middle, within white or pale pink ; margin 

 crenulate at the larg-er end : beak oblique, near the larger end. 



315. M. discrepant. Sub-oval, compressed, rounded and 

 broader at the anterior end, striate longitudinally on 

 both sides and transversely in 'he middle. 



Montague Brit. Shells'p. 169. n. 11. Linn. Trans, viii. t. 3.7. 9. 

 SMI refembling the last, but is less, covered with an olive-green 



