P E R N A 



Plate V. 



Species 20. (T\Ius. Cuming.) 

 Pern'a Rvms. Pei-n. testa, subjlexuoso-elongald, rude la- 



miuaid, umbonihus rostratis, purpureo-fuscd. 

 The uude Perna. Shell somewhat flexuously elongated, 

 rudely Imuiiiated, umboes beaked, purple-brown. 



Hah. ? 



Of a flexuously elongated form, composed externally of 

 rude concentric lamiu.'e, rather barren of character. 



Species 21. (Mus. Cuming.) 



Perna Vulsella. Pm-n.te.dd elongato-quadratdjingua- 

 fonni, lavi, nitente, livido-fuscescente, albo radiatim 

 limatd et fa^ciatd, iimboiiibus parvis, aduncis. 



The Vulsella Perna. Shell elongately square, tongue- 

 shaped, smooth, shiniug, livid-brown, radiately liue- 

 ated and banded with white, umboes small, hooked. 



Lamarck, Anim. sans vert. vol. vii. p. 7S. 



Hab. ? 



Distinguished by its smooth surface and white-banded 



p<ninting, and by the small hooked character of the umboes. 



Species 22. (Mus. Cuming.) 

 Perna legumen. Fern, testa elongato-linguceformi, ver- 

 sus umbones rude concentrice lamhiatd, deinde lavigatd, 

 irregidari ; sordide ulbd. 

 The pod Perna. Shell elongately tongue-shaped, rudely 

 concentrically laminated towards the umboes, then 

 smooth, irregular ; dull-white. 

 Ostrea legumen, Gmelin, Syst. Xat. p. 3399. 

 Eah. Lord Hood's Island ; Cuming. 



Of a curiously elongated pinched growth, of a dead- 

 white colour, the laminte being first ai-ranged concentrically 

 and afterwards irregularly blistered. 



ecies 23. (Mus. Cuming.) 



Pern, testd oblique ovatd, antice late 



Pekna fimbriata 



alatd, Icevigatd, versus margineiti tmdiqae fimbriata et 

 subsquamald ; lutescente-albd, versus marginem livido- 

 purpureo tinctd et radiatd. 



The fimbriated Peena. Shell obliquely ovate, ante- 

 riorly broadly winged, smooth, everywhere fimbriated 

 and finely scaled towards the margin; yellowish-white, 

 stained and rayed towards the margin with livid- 

 purple. 



Hab. Moluccas. 



The obliquely ovate, broad-winged form of this species 



is peculiar, and its fimbriated sculpture is characteristic. 



Species 24. (Mus. Cuming.) 

 Perna isognomum. Pern, testa elongatd, plerumque sub- 

 fiexuusd, depressd, rude laminatd, basi antice anguste 

 alatd, aid plus minus ciirvatd, postice abrupte late si- 

 nuatd ; purpurevnigrd. 

 The carpenter's square Perna. Shell elongated, 

 generally rather flexuous, depressed, rudely laminated, 

 base narrowly winged anteriorly, wing more or less 

 curved, posteriorly abruptly broadly siuuated ; purple- 

 black. 

 Ostrea isognomum, Linnaeus, Syst. Nat. p. 1149. 



Varietates P.femoralU and caninn, Lamarck. 

 Hab. Philippine Islands ; Cuming. 



This well-known species varies in having the wing some- 

 times longer, with the body of the shell less elongated than 

 in the specimen figured. Sometimes the shell is even 

 more elongated than this, in which case the wing is 

 almost obsolete. 



November, 1S58. 



