AVICULA. 



Species 68. (Mus. Cuming.) 



AvicULA Placunoides. Jvic. testa longitudimliter 

 Qvuld, siiperne subquadrata, tenui, semipellucidd, plana, 

 mbconwa, lutescente-albd, fasciis angustis opaco-albis 

 midaiis radiata, nigricante-purpureo promiscue ma- 

 culaid. 



The Placuna-like Avicula. Shell longitudinally ovate, 

 sonaewhat square at the upper part, thin, semitrans- 

 parent, flat, rather horny, yellowish-white, rayed 

 with narrow waved opake white bauds, promiscu- 

 ously blotched with blackish-purple. 



ITab. Australia. 



Remarkable for its thin Flaciim-like structure, rayed 



irregularly with waved opake bauds, and promiscuously 



blotched with purple-black. 



Species 69. (Mus. Cuming.) 



Avicula libella. jivic. testa oblique orbictdari, valde 

 convexd, aid gracili, elongatd ; lutescente-corned ; epi- 

 dermide serratd minute foliatd indutd. 



The deagon-fly Avicula. Shell obliquely orbicular, 

 very convex, with a long slender wing; yellowish- 

 horny ; covered with an elaborately festooned serrated 

 epidermis. 



Hab. China Seas. 



A semitransparent, horny, clongately-winged shell, most 



elaborately festooned with a minutely-sen-ated epidermis. 



Species 70. (Mus. Cuming.) 

 Avicula vexillum. Avic. testa oblique quadratd, inar- 



quivalvi, pellucido-corned, tenuissimd, sirigis amplis 



purpureo-nfis marnioratd. 

 The flag Avicula. Shell obliquely square, inequivalve, 



transparent horny, very thin, marbled with large 



purple-red streaks. 

 Hab. Ceylon (in deep water) ; Gardner. 



A shell of very transparent substance, boldly marked 

 with promiscuous dark stripes, destitute of any winged 

 appendage. 



Species 71. (Mus. Cuming.) 



Avicula pica. Avic. testa trigono-ovatd, crassd, convexd, 

 Icsvigatd, virescente-albd, radiis nigricante-purpureis 

 irregularibus marnioratd, margine laminari, intus con- 

 spiciie pica. 



The pied Avicula. Shell triangularly ovate, thick, con- 

 vex, smooth, greeuish-white, marbled with irregular 



blackish-purple rays, margin laminar, conspicuously 



pied within. 

 Gould, Moll. U. S. Exploring Expedition, p. 443. pi. 39. 



f. 599. 



Avicula maeulata, Gould. 

 Hab. Pitcaim's Island. 



A species of solid structure, inlaid with an extremely 

 delicate yellowish nacre, remarkable for its prolonged 

 laminar margin being conspicuously pied. 



Species 72. (Mus. Cuming.) 



Avicula maura. Avic. testa oblique oblongd, tenui, la- 

 vigatd, nitente-nigrd, alba sparsim vmrmoratd, epider- 

 mide decidud minute serratd, aid subproductd. 



The moor Avicula. Shell obliquely oblong, thin, 

 smooth, shining-black, sparingly marbled with white, 

 minutely-serrated deciduous epidermis, wing rather 

 produced. 



Hub. Sydney. 



A thin, shining, jet-black shell, with a finely serrated 



thick-set epidermis on the ear. 



Species 73. (Mus. Cuming.) 



Avicula cornea. Avk. testa oblique oblongd, convexius- 



culd, olivaceo-corned, Icevigatd, aid laiiusculd. 

 The horny Avicula. Shell obliquely oblong, rather 



convex, olive, horny, smooth, wing rather broad. 

 Ilab. Jamaica; Gosse. 



A plain, olive, horny shell, moderately winged, attach- 

 ing itself to Gorgonia. 



Species 74. (Mus. Cuming.) 

 Avicula fucata. Avic. testa longitudinaliter oblongd, 



subquadrata, convexd, tenuiculd, purpureo-rufo dense 



radiatd, laminis tenuibus planis concentricis nmpliter 



serratis obsitd. 

 The stained Avicula. Shell longitudinally oblong, 



somewhat square, convex, rather thin, closely rayed 



with purple-red, beset with thin, largely seiTated, 



flat, concentric laminse. 

 Gould, Pro. Bost. Soc. Nat. Hist. vol. iii. p. 309 ; Moll. 



U. S. Exploring Expedition, p. 441. pi. 39. f. 551. 

 Hab. Japan. 



Chiefly distinguished by its radiating pattern of red 



June, 1857. 



