1880.] MR. E. A. SMITH ON THE GENUS MYODORA. 583 



This form is scarcely separable from M. trigona. It is, however, 

 a trifle more oblong, with the apical angle hardly as acute and the 

 concentric ridges of the deep valve fewer and more distant. 



11. Myodora fluctuosa, Gould. 



Myodora fluctuosa, Gould, Proc. Bost. Soc. Nat. Hist. 1861, 

 vol. viii. ; Otia Conch, p. 1(J1. 



Hab. Japan, Kagosima Bay. 



This species is known to me only by Gould's description, which 

 runs thus : — " T. parva, tenuis, albida, umbonibus fere medianis : 

 valv. dextra couvexa, postice triangularis, apice truncata, undulis 

 concentricis circ. 20 ad margines baud protractis ornata ; (valva 

 sinistra ignota ;) cardo debilis, dentibus elongatis. Long. 8, alt. 7, 

 lat. 3 millim." 



12. Myodora convexa, Angas. 



Mt/odora convexa, Angas, Proc. Zool. Soc. 1865, p. 57. pi. ii. 

 f. 13-14. ^ 



Hab. New Caledonia. 



This species, as its name implies, has the deep valve very convex. 

 It is of a rather rounded form and finely regularly lirated. 



13. Myodora tasmanica, Woods. 



Myodora tasmanica. Woods, Proc. Roy. Soc. Tasm. 18/5, 

 p. 160. 



" Testa albida, curvato-oblonga, aniice leviter fiexuosa, abrnpte 

 truncata, valva sinistra ventricosa-convexa, dextera distincte 

 concava; concenirice striata ; striis paucis, rotundatis, latiusculis, 

 subdistantibus, regulariter cresceniibus ; sub lente elegantissime, 

 tenuissime decussata. Long. 17, lat. 13, alt. 4 mill." 

 Hab. Long Bay, Tasmania. 



" This very distinct species of Myodora has more affinities with 

 the Australian M. pandorceformis than any other ; but it has no 

 movable testaceous apjJendage, and the valves are both distinctly 

 striately ridged" {Woods). 



The above description applies exactly to M. ovata, which, how- 

 ever, is said to be from the Philippine Islands. 



14. Myodora albida. Woods. 



Myodora albida. Woods, Proc. Roy. Soc. Tasman. 1875, p. 160. 

 " M. testa alba, transliicida, subquadrate oblonga, subconvexa, 

 antice latissime truncata ; co7icentrice striata ; striis elevatis, 

 rotundatis, regidaribus, paucis, jyrope marginem anticum angulatis. 

 Long. 10, lat. 6, alt. 2 mill." 

 Hab. Long Bay, Tasmania. 



" A very pretty species, differing from the last in its subquadrate 

 form and its convex valves, which are both regularly and distinctly 

 striate" (/rooc/s). 



