124 PLEUROBRANCHID, 
sometimes eight lines long ; colour on the sides pale greyish-brown, 
passing on the back into a dull sea-green ; the whole surface with 
numerous irregularly shaped black blotches that are longest on the 
back. Along the back a double row of eight-twelve emerald green spots, 
each surrounded with a zone of umber; dorsal tentacles three-quarter 
inch long, folded so as to appear tubular ; labial tentacles similar in 
shape but larger; foot long and narrow, pointed behind, without side 
lobes ; sole pale sea-green (Cheeseman.) 
Auckland. 
FAMILY—PLEUROBRANCHID. 
Head with auriform tentacles ; eyes sessile on the head, at the bases 
of the tentacles ; mouth provided with an oral veil, corneous jaws, and 
an armed radula.. Gills composed of a double row of leaflets in the 
form of a long branchial plume at the side of the body under the edge 
of the mantle. Shell calcareous and external, membranous and internal, 
or wanting. No upper jaw; teeth short, arranged in a quincunx. 
Genus, PLEUROBRANCHUS—Cuvier. 
Tentacles dorsal, ear-like ; labial appendages transverse, folded and 
truncate ; mantle smaller than the foot, only partly covering the head, 
simple behind, covering and concealing the shell. Foot very large, 
extending beyond the mantle. Shell internal, thin, oval, mem- 
branaceous. 
P. ornatus, Cheeseman, P.Z.S., 1878, p. 275, pl. xv., f. 1-2. Body 
three-four inches long, depressed, nearly equally rounded at both ends ; 
colour varying from pale buff to a clear reddish-brown, with irregular 
blotches of rich dark red-brown; mantle large, extending over and 
concealing both head and foot, quite smooth; margin thin, entire ; 
dorsal tentacles short, stout, abrubtly truncate, finely transversely 
wrinkled, approximate at their origin, but diverging, reddish-brown 
tipped with white; eyes black, placed a little distance behind the 
tentacles ; oral tentacles, united by a thin veil concealing the mouth, 
and carried in advance of the foot. Shell half to three-quarter inch long, 
squarish oblong, thin, and membranous, semi-transparent, slightly irides- 
cent, closely marked with somewhat irregular concentric strize ; colour 
white or brownish (Cheeseman. ) 
Genus, PLEUROBRANCHZA—Meckel. 
Tentacles dorsal ; eyes none ; labial appendages united by a narrow, 
transverse oral veil; mantle indistinct, indicated by a narrow band on 
the right side ; anal orifice above the gill; foot narrow. Shell none. 
P. nove-zealandiz, Cheeseman, P.Z.S., 1878, p. 276, pl. xv. 
SI 33 Trans. N.Z. Inst. xi. p. 375. Body oval, convex, thick and fleshy, 
smooth, but the whole surface covered with minute puckers and folds ; 
colour light grey, with anastomosing lines of dark greyish-brown, and 
