TRINE MYTFLACEA. 23-5 



M. Elegans. Gray. Spic. Z. t. 6./. 14. Thin, slender, pel- 

 lucid, pale green, posteriorly attenuated rounded, anteriorly dilated; 

 hinge margin straight, the anterior dorsal part finely rayed and 

 transversely waved with purple, rest of the shell smooth. 1|. 

 Africa. 



M. Metcalfei. Nobis Z. P. 1844. Subtriangular-oblong, ven- 

 tricose, covered with a yellowish brown epidermis, which is glossy 

 except upon a narrow strip adjacent to the ligamental edge, and a 

 lunule-like spot at the posterior end; anterior area much com- 

 pressed, obsoletely bearded, reddish purple ; posterior surface 

 bluish white ; umbonal ridge very prominent and obtusely subca- 

 rinated near the acute and purple beaks ; dorsal edge straight, much 

 elevated, forming a distinct angle with the nearly straight and sub- 

 equal anterior edge ; anterior extremity rather attenuated and 

 rounded ; ventral edge subcentrally incurved ; posterior extremity 

 very narrow, short, but very prominent, and curving towards the 

 beaks ; inside stained with purple anteriorly. If. . 3. Philippines. 



M. Australis. Gray in King's Australia. Inclined to oval, 

 greatly attenuated and extremely short posteriorly, bearded, ven- 

 tricose, under the tawny cuticle which becomes chesnut at each ex- 

 tremity, the anterior slope purplish crimson ; dorsal edge elevated, 

 rather short forming an obtuse angle with the elongated anterior which 

 is scarcely, if at all, incurved; ventral edge but slightly incurved : 

 umbonal ridge only prominent near the narrow umbones : anterior 

 extremity much produced but decidedly obtuse ; inside purplish. 

 2. . S. — Australia. — Shape intermediate between Modiolus and Tu- 

 lipa. 



M. Philippinarum. Nobis Z. P. 1844. Ovate-oblong, tumid, 

 nearly smooth but bearded anteriorly, the cuticle of a tawny colour 

 becoming darker at the sides, and glossy excepting upon a lunule-like 

 space at the tip of the rather prominent and rounded posterior ex- 

 tremity ; dorsal edge elevated, but slightly convex, rather long 

 forming a distinct but very rounded angle, with the nearly straight 

 and slightly incurved anterior edge ; ventral edge with a dilated 

 incurvation; anterior extremity broad and rounded ; beaks narrow, 

 the umbones elevated and the umbonal ridge very conspicuous ; 

 within dark purple anteriorly. 2±. . 4. Philippines. Somewhat 

 like Modiolus. 



M. Biradiata. Nobis. Z. P. 1844. Oblong-triangular, ventri- 

 cose, smooth, glossy, under a fulvous or brownish olive epidermis 

 (which does not quite reach the nearly straight elongated and ele- 

 vated hinge margin) reddish purple anteriorly, with a narrow white 

 radiating streak beyond the very prominent umbonal ridge ; the 

 shell from thence becomes pale brown with a pale ray just before 

 the posterior extremity which is rather short, but prominent, very 



