140 NOTARCHUS. 
. 
tinct neck, and furnished with four elongated, linear, distant tenta- 
cles, more or less ornamented with papille, mouth beneath, the lip 
dilated laterally into an acutely conical process, like a third pair of 
tentacles. (d.) 
The papille on the mantle are capable of being individually 
elongated and contracted, as they are in Cvprea. 
Distribution, Indo-Pacific region. These animals live on floating 
sea-weed, away from the shore. The exact status of the group, and » 
its relation to Notarchus and Aclesia, can be ascertained only by 
more exact investigation of material. I have seen none of the spe- 
cies. 
Most described forms are decorated with ocelli or eye-spots, and 
all but NV. longicauda have simple or branching processes of the in- 
tegument. In alcoholic specimens the lip-processes characteristic of 
the group are sometimes retracted ; but they are never so strongly 
developed as in Aclesia. 
N. LInEOLATus Gould. PI. 29, figs. 37, 38, 39. 
Length three and a half inches. Animal elongated, delicately 
attenuated posteriorly, of a pale grass green color, ornamented with 
longitudinal, parallel, contorted, rusty lines, and scattered ocelli of 
unequal size. The papille of the mantleare branching. The ante- 
rior tentacles are short, tapering, and destitute of papille. (Gid.). 
Honolulu, Oahu, on a coral reef. 
Stylocheilus lineolatus Guv., U. 8. Expl. Exped., Moll., p. 225, pl. 
16, f. 270, a (1852) ; Otia Conch., p. 227. 
Dr. Pickering, who observed this animal, remarks that the creep- 
ing disk is very long, ending in a sharp point. Branchial cavity 
generally kept pretty wide open; the branchiz are very large, not 
covered by a dorsal plate, and colored above in the same manner 
as the mantle, and they are inflated as though injected with water. 
The heart is seen beating on the left side, immediately under the 
origin of the branchiz. The vent projects much as in Doris. The 
lines on the surface were more or less concentric, like the striz in 
the palms of the hands. Motion quite active. 
Though the two figures differ somewhat in their details, I judge 
them to represent the same species. In the dark green one, the 
tentacles are shorter, and the cephalic pair are destitute of papillee, 
and the papille are branched. In the pale one (fig. 37), the ten- 
