74 TETHYS—EUROPEAN. 
ample, and its opening is very small. Siphon as in Jeporina, long; 
and over its inner right wall lies a very large anal opening. Gillas 
figured by Blochmann for depilans. Genital opening lies under the 
gill-cover a little in front of the gill, as in other Aplysias. Sperm- 
groove ends a little before the right tentacle, as in leporina and 
chierchiana. The tentacles show nothing characteristic. The radula 
is lancet-shaped, with 37 rows, the median ones with 41°1°41 teeth. 
Penis similar in shape to that of depilans, but it is not black (in 
alcohol), and its sheath does not show the papille as in depilans. 
The opaline-gland (or gland behind the genital opening) consists of 
a group of one-celled glands, each with its separate efferent duct, as in 
depilans, lessoni and punctata. 
Shell 75 mill. long, very thin, entirely transparent and almost 
without chalky layer. In general it agrees nearly with that of 
leporina. 
Bay of Posilippo, Gulf of Naples (Lo Bianco). 
Aplysia lobiancoti MaszARELLI, Nachrichtsbl. D. Malak. Gesell- 
sch. xxii, 1890, p. 42. 
This species seems to have been described from one alcoholic spec- 
imen, scarcely to be distinguished from /eporina in external anatomy, 
but with the opaline gland and penis more as in depilans. It can 
hardly be regarded as well founded until living specimens are de- 
scribed, and the anatomical features are found to be constant. 
T. MaRMoRATA Blainville. Pl. 33, figs. 26, 27, 28, 29. 
Length about 60 mill. Oval, smooth, the foot acute behind. 
Swimming-lobes large. Mantle broad with a median tube; the ex- 
current siphon conic and quite long. Color, obscure greenish, mar- 
bled with black spots. 
Shell ovate, elongated, very concave, nearly membranaceous, or 
at least with a slight calcareous layer readily lost in alcohol; buff 
livid; apex feebly curved toward the upper sinus of the shell, which 
is far back and little arcuate. Length 20 mill. 
West coast of France ; Bayonne, Rochelle, ete. 
A. marmorata BLAINv., Dict.Se. Nat. xxvi, p. 326 (1823) ; Journ. 
de Phys., Vol. 96, p. 286, f.3, 4—Rana, Hist. Nat. Aplys., p. 58, pl. 
12, f. 6-9. 
I have not seen thisspecies. It will probably group near leporina. 
