A M P H I D E S M A . 



Plate IV. 



Species 31. (Mus. Cuming.) 



Amphidesma Geuneri. Ampli. testa suioiligue ovatd, 

 crasm, convexkisculd, albidd, rosea promiscue maculatd 

 et radiatd, latere antico vlx longiore, postico rotmidato, 

 subjlexuoso ; coiicentfice plicntd, plicis dense tenuila- 

 mellods, lamellk quasi abrasis, interstitiis liris parvis 

 concinne radiatis. 



Geunee's Amphidesma. Shell somewhat oblique, ovate, 

 thick, rather convex, whitish, promiscuously blotched 

 and rayed with rose, anterior side scarcely the longer, 

 posterior rounded, subflexuous ; concentrically pli- 

 cated, plaits densely finely lameUated, the lamellai as 

 though abraded, interstices finely rayed with small 

 ridges. 



Semele Gi-uneri, A. Adams, Pro. Zool. Soc. July, 18.53. 



Hab. ? 



A beautiful rose-painted species, plaited concentrically 

 with ribs of closely packed lamellae, the interstices l)etvveeii 

 the ribs being raved with fine ridges. 



Species 22. (Mus. Cuming.) 



Amphidesma pallid.^. Amph. testa ovali, palUde pur- 

 purascenie-fidvd, umbonibics saturatioribus, tenuissime 

 concentrice striata, epidermide tenui subiridescente in- 

 dutd ; latere postico subtruncato, jlexuoso, antico ro- 

 tundato. 



The pale Amphidesma. Shell oval, pale purple-fulvous, 

 umboes darker, very finely concentrically striated, co- 

 vered with a thin subiridescent epidermis ; posterior 

 side subtruncated, flexuous, anterior rounded. 



Sowerby, Pro. Zool. Soc. 1S33, p. 199. 



Hah. Salango, West Columbia (dredged in sandy mud at 

 a depth of seven fathoms) ; Cuming. 



Extremely finely sculptured throughout with close-set 

 concentric raised stria:). 



Species 33. (Mus. Cuming.) 



Amphidesma decussata. Amph. testa subtrir/ono-orbicu- 

 lari, tenuieuld, latere postico subanyidato et Jle.viioso; 

 albidd, prope umbones purpura scente tinctd, intus pur- 

 purea vivide tindato-punctatd ; radiatim minute striata, 

 lineis tenuibus elevatis cancentricis versus marginem. 



The decussated Amphidesma. Shell somewhat tri- 



angularly orbicular, rather thin, posterior side sbghtly 

 angled and flexuous ; whitish, tinged with purple to- 

 wards the umboes, brightly wave-dotted with pm'ple 

 in the interior ; radiately minutely striated, with thin 

 raised concentric lines towards the margin. 



Tellina decussata, Wood General Conch, p. 190. pi. 43. 

 f. 2 and 3. 

 AmpJddesma Jayanum, C. B. Adams. 



Hab. West Indies ; C. B. Adams. 



A delicately formed species, tinged externally with pur- 

 ple towards the umboes, from a sprinkling of rose-purple 

 wave-dots in the interior showing through. 



Species 24. (Mus. Cuming.) 

 Aaiphidesma decisa. Ampli. testa stMrigono-orbiculari, 

 compressd, latere postico subangulato et conspicue Jlex- 

 uoso, concentrice j)ecidiariter rucle plicatd, plicis tumidis, 

 irregnlaribus, undiqiie crispato-punctatis, quasi corru- 

 gatis; roseo-albidd, plicarum interstitiis liic illic roseis. 

 The decided Amphidesma. Shell somewhat triangu- 

 larly orbicular, compressed, posterior side rather an- 

 gled and conspicuously flexuous, concentrically pecu- 

 liarly rudely plicated, plaits swollen, irregular, and 

 crisply dotted, as though wrinkled, throughout ; pink- 

 ish-white, interstices between the folds here and there 

 pink. 

 CoNEAD, Journ. Acad. Nat. Sci. Philadelphia, vol. vii. 



pi. 19. f. 2. 

 Rab. San Diego, California. 



This fine and very characteristic species is most curi- 

 ously wrinkle-punctured throughout. 



Species 23. (Mus. Cuming.) 



Amphidesma Zebuensis. Amph. testa oblongo-ovali, in- 

 cequdaterali , coinpressiusculd, latere antico sublongiore, 

 rotmidato, postico subtruncato, paululumflexuoso ; al- 

 bidd, carneolo promiscue pallide radiatd ; concentricK 

 lamellato-costatd, cosiis aubcequalibus, ad latera pro- 

 ductis, interstitiis minutissime striata -radiatd, lined 

 elevatd concentricd. 



The Zebu Amphidesma. Shell oblong-oval, inequila- 

 teral, rather compressed, anterior side somewhat the 

 longer, rounded, posterior subtruncated, a little flexu- 

 ous ; whitish, promiscuously raised with faint flesh- 



October, 1853. 



