AglaJT,."] GASTROPODA. 543 



Distribution. Mediterranean, east coast of Africa, Australasia, 

 Japan, Sandwich Islands, west coast of the Americas, West Indies. 

 The genus is not known fossil. 



1. Aglaja cylindrica, Cheesman. 1881. Plate 23, figs. 10, a, b ; 

 Plate 37, fig. 1. 



Melanochlamys cylindrica, Chsrn., T.N.Z.I., xiii, 1880 (1881), 224. Aglaja 

 cylindrica, C'hsm., Man. Conch. (1), xvi, 49. 



Body elongated, almost cylindrical, 1-1 j in. long ; colour a deep 

 rich velvety black. Cephalic disc narrow, oblong-quadrate, slightly 

 expanded in front, so as to project over the foot and mouth, truncate 

 behind. Mantle small, entirely concealing the shell, at its posterior 

 end two-lobed and with a large gaping orifice. Foot large, with 

 ample side lobes, which are folded up to the sides of the head-disc 

 and mantle, leaving, however, the back exposed. Branchicr minute, 

 situated far back on the right side under the mantle. Gizzard very 

 large and muscular, without calcareous plates. Odontophnre apparently 

 wanting. (Cheeseman.) 



Shell calcareous, white ; spire small, s'olute. with a small spoon- 

 shaped projection ; lower lip membranous. 



Type(l). 



Hab. In tide-pools near the Tamaki Heads, Auckland Harbour, 

 type (Cheeseman) ; Dunedin Harbour (G. M. Thomson). 



Tribe 2. APLYSIOMORPHA. 



In these Tectibranchs the -shell is always much reduced and more 

 or less internal, or it may be altogether lost in the adult. The head 

 bears 2 pairs of tentacles. The margins of the foot, or parapodia, 

 are separate from the ventral surface, and are generally transformed 

 into natatory lobes. The genital duct with 1 pore ; the herma- 

 phrodite duct is connected with the verge by a ciliated groove. The 

 animals comprised in this tribe are crawling or swimming forms. 



Fam. APLYSIID^, d'Orbigny. 



Animal lengthened, not protected by a shell, the neck and head 

 narrower than body, mouth a vertical fissure ; anterior angles of head 

 produced in 2 tentacular lobes folded above ; behind them the cylindric 

 or conical rhinophores slit above, in front of which are the minute 

 eyes. Epipodia or pleuropodia recurved over the back, forming 2 

 lateral or dorsal lobes enclosing mantle and gill. Genital orifice 

 within the dorsal slit, communicating by a long furrow with the in- 

 vertible verge, which is near the anterior right tentacle. Mouth with 

 corneous jaws and a large multiserial radula composed of similar 

 teeth ; stomach armed with cartilaginous nodules ; anus behind the gill. 



Shell nearly or entirely covered by the mantle, uncoiled, in the 

 form of a concave plate, sometimes absent. 



