M A C T R A 



Plate XIX. 



Species 102. (Mus. Cuming.) 



Mactra nucleus. Bluet, testa trigono-quadratd, com- 

 pressd, cequilaterali, sqtmlide alba, ; umbonibus submu- 

 cronatis ; luindd aredque angustls, dedivis, imlidbictis. 



The kernel Mactra. Shell triangularly square, com- 

 pressed, equilateral, dirty white ; umboes rather 

 pointed ; lunule and area slanting, narrow, indistinct. 



Conrad, Journ. Acad. Nat. Sci. Philadelphia, vol. 6. pi. 

 11. f. 4. 



Hab. Bay of Manilla ; Cuming. North America ; Conrad. 



A minute triangularly square compressed species, the 

 smallest of the srenus. 



Species 103. (Mus. Cuming.) 



Mactra Corbuloides. Mad. tedd trigoiio-ovatd, gib- 

 bosiuscidd, inaqiiilaterali, Ifeviyatd, alba, niteiite, la- 

 tere antico rotundato, postico late trigono, arcuato-ros- 

 Irato ; lunula minima, area maxima. 



The Corbula-like Mactra. Shell triangularly ovate, 

 rather gibbous, inequilateral, smooth, white, sliining, 

 anterior side rounded, posterior broadly angled, arcu- 

 ately beaked ; lunule very small, area very large. 



Deshayes, Pro. Zool. Soc. 1851>. 



Hab. ? 



Distinguished by a broad concavely beaked area, while 

 the lunule is almost obsolete. 



Species 104. (Mus. Cuming). 



Mactra eostrata. Mad. testd trigond, gibbosiusculd, 

 hiaquilaterali, sordide alba, IcBvigaid, latere antico 

 rotimduto, poderiore angulato-rodrato ; lunula vlx 

 nulla, ared magna, lata. 



The beaked Mactra. Shell triangular, rather gibbous, 

 inequilateral, duU white, smooth, anterior side 

 rounded, posterior angularly beaked ; lunule scarcely 

 any, area large and broad. 



Spengler, Skrift. Naturch. Selsk. vol. 5. p. 115. 



Hab. Moreton Bay, Australia ; Strange. 



Very similar to the preceding species, but shorter and 

 more gibbous in form. 



Species 105. (Mus. Cuming.) 

 Mactra Apheodina. Mad. testd transversa, ovato-tri- 



May, 



go7id, temii, depresuusculd, inaquilaterali, pallide vio- 

 laccd, zomdis transvenm saturatioribus irregulariter 

 interrnptd, transversim regulariter eleganter striata, 

 latere antico pauluhmi atlenuato, superne redo, declivi, 

 postico aqualiter obtuso ; umbonibus minimis, aadis, 

 albidis ; cardine angnsto, violaceo, utroque latere ma- 

 culato ; fossidd minimd, angustd, obliqud ; dentibus 

 lateralibus lam.ellosis ; valvis intus vivide violaeeis, in 

 medio paUidioribus ; impressione pallii maryine itife- 

 riore remoto, si/iu angusto, brevi, liorizontali. 



The Apheodine Mactra. Shell transverse, ovately 

 triangular, thin, rather depressed, inequilateral, pale 

 violet, irregularly interrupted with darker transverse 

 zones, transversely regularly elegantly striated, ante- 

 rior side a little attenuated, straight at the upper 

 part, slanting, equally obtuse with the posterior ; um- 

 boes very small, sharp, whitish ; hinge narrow, violet, 

 spotted on both sides ; pit very small, narrow, ob- 

 lique ; lateral teeth lamellous ; valves deep violet 

 within, paler in the middle ; impression of the mantle 

 with the lower edge remote, sinus narrow, short, 

 horizontal. 



Deshayes, Pro. Zool. Soe. 1854. 



Hab. China Seas ; Belcher. 



A peculiarly polished CiiUierea-X\ke, species, of a hvid 

 grey colour, obscurely banded. 



Species 106. (Mus. Cuming.) 



Mactra scalpellum. Mad. testd trigono-oblongd, lenui, 

 ralde compressd, cequilateruli, Icevigatd, niteiile-albd, 

 extremitatihis subattemiaio-rotundatis ; umbonibus mi- 

 nimis, approximatis ; lunuld aredque angustissiiuis, in- 

 dislindis, plicato-striatis. 



The lancet Mactra. Shell triangidarly obloug, thin, 

 very compressed, equilateral, smooth, shining white, 

 extremities rather attenuately rounded ; umboes very 

 small, close ; lunule aud area very narrow, indistinct, 

 plicately striated. 



Deshayes, Pro. Zool. Soc. 1854. 



Hab. New Zealand; Strange. 



A thin compressed species with a white polished surface, 

 having very much the appeai'ance of a Tellina. 



1854. 



