TETHYS-INDIAN OCEAN. 109 
Aplysia tigrina Rane, Hist. Nat. Aplys., p. 57, pl. 11.—Desu., 
Moll. Réun., p. 54.—Marr., in Mobius, p. 307. 
This is not the A. tigrina of Quoy & Gaimard, nor of Angas and 
Sowerby. Ido not know whether it is that of Deshayes and von 
Martens or not. 
T. TIGRINELLA Gray. PI. 16, figs. 5, 6. 
Body elevated, greenish, very lucid, reticulated with brown, 
with scattered spots and little lines of black. 
Because our individual, the drawing of which was made from the 
living animal, offers some differences from that of Rang, we include 
it here. Its length is six inches; back very much swollen. The 
swimming lobes smooth, always elevated, form a sinus extending 
from behind the tentacles nearly to the tail. The foot is narrow, 
the head short, and the tentacles are not much developed. The 
ground color is a clear, diaphanous green, reticulated with spots of 
bistre, in the midst of which are black dots or little lines. The 
head is more regularly reticulated. 
The shell is broad, oval, a little concave, leathery, very finely 
striated, with the beginning of a spire; its edges are entirely mem- 
branous. 
Port Louis, Mauritius. 
Aplysia tigrina Quoy & GaimaRD, Voy. de l’Astrol. Zool., ii, p. 
308, pl. 24, f. 1, 2 (1832).—A. tigrinella Gray, Systematic arrange- 
ment of the Figures, in M. E. Gray’s Figures of Molluscous Ani- 
mals, iv, p. 97, No. 27 (1850) ; referring to Vol. i, pl. 61, f. 4, copies 
of Quoy’s figures cited above. 
My information and figures, like Gray’s, are derived entirely 
from Quoy’s account of thisform. It differs strikingly from Rang’s 
A. tigrina in the shell (compare pl. 16, figs. 4 and 6), and there are 
also differences in the soft parts. Quoy’s figure from life shows 
short finger-like processes scattered over the outer surface of the 
swimming lobes, like a Notarchus, although his description men- 
tions no such structure. The species appears, however, to be clearly 
distinct from A. tigrina Rang, and the name proposed by Gray is 
therefore adopted. 
T. NoDIFERA Adams & Reeve. PI. 16, fig. 1. 
Dull olivaceous, covered with numerous rather distant elevated 
tubercles ; painted with pale violaceous sparse spots, the foot orna- 
