LEPIDOPLEUR1 3. 



thin, narrow, and sparely 96l with small pel- 

 lucid ipiculea Dear the mar-in. Ti ior mucro or up. 



lllr [Tile, in ^flop^ is prominent, overhangs a shallow 



J ami fV.., n its point there diyerp- anteriorly t\mr depr 



the anterior lateral an-l.-> of tin- plate, the 



inn. :idi-tant from each ot her and the outer Iiu,->. I'.etween 



the plat.- ^ >welled, formini: three rounded ridges, 



ruard like th.- leaflet- of a trefoil <r clover, Nothing 



iiblm- thi> ha> been !> rvcd on any of the other species which 



have oome under my notice. The >,,ft parts in spirits appeal- to 



Other Bpeciefl compared with it. It is evidently adult 



Tl '' Bent the form dredged l.y the 'Challen-er 1 ,,tr 



m t Thilippines. Had.lon describes these specimens a< fullcws: 

 S|l(l11 - l>nttl.-. cloaelj Covered with larire, round, .smooth tuber- 

 i an angle of about 110. Sutural lamina- 

 all. 



r valve. With a few irregular lines of r row th, thickly 



A ilh irregularly disposed tubercles. 



' li:ltt> v ^' ntral areas: with a shallow depression 



: -h Bide "f the median rid^., which givea the latter a pinched 



: his depn-sion is mo>t apparent at the hinder border 



The tubercles have a -eneral arrangement in 



ol.li.ju,' liiu-s ra.liatin- forwards from the keel and at the same time 



i" li' Btric to the umbo, but these two series of lines are not 



'. and the tubercles often appear to be irregularly dis- 



!' short eoncentric rows usually demarcate the 



1 the lateral areas. Lateral areas: scarcely ap- 



ndicatin.i: a line of -rowth occurs at a short dis- 

 Mle; tubercles irregularly disposed, with a ten- 

 '.. however, to concentric lines. 



With a small subeentral umbo, behind which 

 Interior area: the lateral lon-itudi- 



""I '' tejugum to be slightly prominent and thus 



give^ the anterior inewhat trilobed appearance; the tuber- 



Bnded keel. Posterior area; with ooncen- 



i and el-.-elv >rt tuber, 



. thickly covered with delicate small oval scales; 

 :ini1 more pointed scales occur along the border 



and in th- !vr> 



