AMPHIDESMA.— Plate I. 



Scmele venusta, A. Adams, Pro. Zool. Society, July, 1S53. 

 Halt. West Columbia. 



An oblong, fiiiutly rayed, TeUina-\ike species, concentri- 

 cally somewhat flexuously grooved throughout. 



Species 4. (Mus. Cuming.) 



Amphidesma coekugata. Ampli. tesld siihorbiculari, 

 crassci, albicante, radiatim striata, concentric^ rngulosu; 

 epidermide fmcd ; niargine dormli podicd recta, incli- 

 natd ; intusjlavescente-aurantid. 



The wrinkled Amphidesma. Shell nearly orbicular, 

 thick, whitish, radiately striated, concentrically finely 

 wrinkled ; epidermis brown ; posterior dorsal margin 

 straight, inclined ; yellowish-orange within. 



SowERBY, Pro. Zool. Soc. 1832, part 2. p. 200. 



Hab. Peru and Iquiqui, South America (dredged from 

 coarse gravel, in ten fathoms water) ; Cuming. 



A fine large solid subdistorted shell, of an unspotted 

 stone-white hue externally, binlliantly coloured within with 

 yellowish-orange. 



Species 5. (Tig. a,b, Mus. Cuming.) 



Amphidesma obliqua. AmpJi. tedd oblongo-orbicn- 

 latd, convexo-depressd, ieniii ; albido-purpiirascente, 

 maculis lituraformibus spadiceis plus minus variegatd, 

 parte untied et mediand liris tenuibus concentrice obli- 

 que sculptd. 



The variegated Amphidesma. Shell oblong-orbicular, 



convexly depressed, thin ; white -purplish, more or 

 less variegated with fawn blotches, anterior and mid- 

 dle portion of the valves sculptured with fine ob- 

 liquely concentric ridges. 



Tellina obliqua, Wood General Conch, p. 152. pi. 41. f. 4 

 and 5. 

 Amphidesma varie(/atu7n, Lamarck. 



Hab. Brazils (in sandy mud at eight fathoms) ; Miller. 



There is an important character in this species un- 

 noticed by Lamarck. The anterior and middle portion of 

 each valve is sculptured with fine concentric ridges, not 

 ranging parallel with the lines of growth, but a little ob- 

 liquely across them, well marked in Wood's figure. 



Species 6. (Mus. Cuming.) 



Amphidesma carnicolor. Ampli. testa orbicidari, 

 latere postico subflexuoso, crassiusculd, pellucido-aUid, 

 intus marginem, versus auratitid, concentrice liratd, liris 

 mdibus, tenuibus, i?tterslifiis nigis dense radiatis. 



The flesh-coloured Amphidesma. Shell orbicular, 

 posterior side a little flexuous, rather thick, transpa- 

 rent white, orange towards the margin in the interior, 

 concentrically ridged, ridges rude, fine, with the in- 

 terstices densely rayed with wrinkles. 



Hanley, Recent Shells, Supp. pi. 12. f. 28. 



Hab. Gundulman, island of Bohol, Philippines ; Cuming. 



A subflexuous rounder species, sculptured with fine, 

 short, irregular ridges, the interstices between which are 

 closely wrinkle-rayed. 



