21a 
Cygnus. 
Maculata, 
Turgida. 
Violacea. 
Cuneata, 
Glauce, 
WORMS. TESTACEA, 6o. Ma&ra. 
Shell much produced on one fide, and gaping at both ends: 
' refembles a Mya: dirty white or yellowifh tinged with orange 
and irregularly clouded with brown: Afage with a {mali and 
large triangular cavity in one valve, and a fimilar cavity with 
an elovence triangular tooth in the other, 
Shell fnowy thick 3-fided, very finely ftriate tranfverfely ; 
the fore-part flattifh and flightly wrinkled: behind the 
beaks a broad heart-fhaped thinly ftriate d ieiien- | 
Chemn. conc. 6. tab. 21, fig. 207. 
Inhabits Tranguebar: an inch long and rather more broad, 
Shell obtufely triangular fmooth thin, with pellucid chefnut 
fpots, within white and very finely ftriate; behind the 
beaks a heart-thaped impretlion., 
Chemn. conc. 6. tab. 21. fig.. 208. 
Inhabits India; about 1 + inch long and rather broader, 
Shell inflated, faintly ftriate, ochraceous and white within; 
beaks diftant purplifh: hinge with a fupernumerary 
triangular double tooth, 
Chemn. cane. 6. tab. 21. fig. 210, 211. 
Inhabits Yranguebar: 2 + inches long, 3 
lucid, jnely ftriate and wrinkled bef ore 
- broad; thin fubpel- 
nd behind. 
E [SIT 
Shell thin, ibisiecdy radiate, finely ftriate tranfverfely ; 1 
margins each fide the beaks whitifh: hinge with a 
fupernumerary double triangular tooth. 
Chemn cont. 6. tab. 22. fig. 213, 214. 
Knorr Vergn. 6. tab. 5. fig. 2? 
Inhabits Zrazgzebar : about 2 inches long and 3 broad, 
Shel! thin oriitlé gaping here ard there, anterior margin oblong 
elevated wrinkled, 
Shell w edges bluc finely ftriate tranfverfely, the mar- 
gin crenulate within. 
Chemn. canc. 6. tab. 22. fg» 213. 
Inhabits refembles the lait, but is only an inch long and 
hardly as much broads fometimes white. 
Shell ovate, dirty white with glacous rays, very finely ftri- 
ate tranfverfely, the anterior part wrinkled. 
Bern Muf. Cas. Vind. test. tab. 36 fig. 31, 12. 
Chemn. conc. 6. tab. 23. fig. 252, 235. 
Inhabits the Mediterranean: 2 3 inches long, 3 I broad: beaks 
4 
turned backwards, with a narrow gare between them, 
Pellucida, 
