CORBULA.— Plate II. 



mity of a Corbula, may serve to protect some alimentary 

 organ analogous to the trunk or proboscis of the animals 

 just alluded to. The umbones of most of the Corbula 

 therefore, upon this principle, are either opposed to each 

 other, or directed posteriorly. 



Species 13. (Mus. Cuming.) 



Corbula tenuis. Corb. testa elongato-oblongd, in medio 

 attenuate, tenui, longitudinaliter profundi striatd ; 

 latere postico declivi-rotundato, latere antico longiore, 

 acutissime angulato-carinato, area sub umbonibus pe- 

 culiariter excavatd. 



The thin Corbula. Shell elongately oblong, attenu- 

 ated in the middle, very deeply striated from end to 

 end; posterior side bent down and rounded ; ante- 

 rior side longer, very sharply angularly keeled, the 

 area between the keel of each valve being pecu- 

 liarly hollowed out. 



Sowerby, Pro. Zool. Soc, 1833. 



Hub. Bay of Montija (dredged from sandy mud at the 

 depth of twelve fathoms) ; Cuming. 

 Mr. Cuming unfortunately met with only a single 



specimen of this curious species. 



Species 14. (Fig. a & b, Mus. Cuming.) 

 Corbula modesta. Corb. testd ovato-rlwmbiformi, la- 

 tere antico paululum productiore, leviter angulato-ca- 

 rinulatd ; longitudinaliter sulcatd, sulcis subprofundis, 

 liris intermediis scalariforniibus ; luteo-violacea out 

 purpurea, radiis albis angustis, ab umbonibus diver- 

 gentibus, eximie ornatd ; intus carneolo -rubra. 

 The modest Corbula. Shell ovately diamond- shaped, 

 anterior side a little produced, and slightly angu- 

 larly keeled ; grooved longitudinally, grooves rather 



deep, the intermediate ridges ranging one upon the 

 other like steps ; yellowish violet or purple, deli- 

 cately ornamented with narrow white rays diverging 

 from the umbones to the margin; interior carnelian- 

 red. 

 Hinds, Pro. Zool. Soc, 1843. 



Hub. Island of Ticao, Philippines (dredged from sandy- 

 mud at the depth of eight fathoms) ; Cuming. 

 This species approximates somewhat closely to the 

 following; it differs in being more solid, and in not 

 having the anterior area so abruptly angulated ; the Cor- 

 bula Taheitensis is also attenuated in the middle, and 

 does not present the same rich carnelian enamel. 



Species 15. (Mus. Cuming.) 



Corbula Taheitensis. Corb. testa ovato-trapeziformi. 

 in medio paululum attenuatd, latere antico abruptc 

 carinato, ared laid, ovatd; longitudinaliter sulcatd, 

 sulcis profundi*, angustis, /iris intermediis scalari- 

 formibus ; lutescente, ab umbonibus pallide radiatd ; 

 intus lutescente. 



The Taheite Corbula. Shell ovately trapeziform, a 

 little attenuated in the middle, anterior side abruptly 

 keeled, area between the keels broad and ovate ; lon- 

 gitudinally grooved, grooves deep and narrow, the 

 intermediate ridges ranging one upon the other like 

 steps ; yellowish, palely rayed from the umbones ; 

 interior yellowish. 



Lamarck, Anim. sans vert. (Deshayes' edit.), vol. vii. 

 p. 139. 



Hub. Island of Taheite, Pacific Ocean ; Lamarck. De- 

 laguete, Island of Zebu, Philippines ; Cuming. 

 I have already spoken of the leading characteristics of 



this species in treating of the preceding, so far, at least, 



as I have been enabled to detect them by examination 



of a single specimen. 



