224 MOLLUSCA. 
tentaculiform process. Foot large and broad, sole yellow, dotted 
greenish. ‘Twice as long as broad, elevated, abruptly sloping behind, 
the foot trailing in a point behind. [1. Pp. c.] 
Length two and a half inches. 
Inhabits the harbour of Rio Janeiro. Couthouy. 
A single specimen found among rocks terminating the beach in 
front of the lagoon of Peteninga, one of those brackish lakes common 
along the coast, separated from the sea by a strip of sand, perhaps fifty 
yards wide, and six feet above high tide. Resembles A. Savigniana, 
Fer., but is distinguished by its broader foot and the filamentous pro- 
longation of the lips, as well as in many of its details. It belongs to 
the genus Notarchus of Cuvier. | 
Figure 269, the animal, as in motion; 2694, view of the plantar 
disk. 
Genus STYLOCHEILUS—(Gourp.) 
Corpus limaciforme, lanceolatum, retrorsum attenuatum, cirrhigerum ; 
caput lberum, tentaculis quatuor elongatis linearibus plus minusve 
papillosis instructum; os inferior; labro laterahter in processum 
subulatum palpiformem dilatato. 
Body limaciform, dilated at the sides and delicately attenuated pos- 
teriorly, cirrhigerous ; head separated from the body by a distinct neck, 
and furnished with four elongated, linear, distant tentacles, more or 
less ornamented with papillz; mouth beneath, the lip dilated laterally 
into an acutely conical process, like a third pair of tentacles. 
Sander Rang, in his remarks on Aplysia longicauda of Quoy and 
Gaimard, says—‘These naturalists have represented six tentacles, 
while in the four individuals preserved, which we have examined, we 
find only four. For light on this subject, we have inquired of M. 
Gaudichaud respecting this apparent error. He answered us, that this 
little animal had three pairs of tentacles; and, to convince us of it, 
showed two outline figures made from the animal, representing un- 
