STRUCTURE AND DEVELOPMENT OF LOXOSOMA. 267 
difficulty. Salensky describes, in the stalk of L. Tethyae and 
in that of L. crassicauda, definite longitudinal rows of gland- 
cells, which have altogether escaped my observation. 
Large oval granular cells are found in the gelatinous tissue 
of the tentacles and other regions of the body of Pedicellina 
(fig. 5, ctp), and have been already mentioned by Nitsche (6). 
In my preparations I can discover no aperture from these cells 
to the exterior, so that it is probable that they are not of the 
same nature as the gland-cells of Loxosoma. 
Foot-Gland. — This structure is eminently characteristic of 
the genus Loxosoma, many species retaining it in the adult 
condition ; whilst in others it is present only in the bud. In 
the former case, when the long axis of the foot lies in a straight 
line with that of the stalk, the “ sole,” by which attachment 
takes place, is on the anterior side, the apex of the foot in its 
usual position being directed posteriorly. 
In L. pes, L. Tethyae, and L. Leptoclini (as well as in 
L. Raja and L. cochlear, Schmidt), the foot is provided with 
wing-like lateral outgrowths (fig. 2, al.). Barrois (13) from 
the presence of these outgrowths, which cannot in reality be held 
to be distinctive of any single species, has given the name of 
Loxosoma alata to a species discovered by him, and states 
that it is identical with L. pes. As there can belittle doubt of 
the specific distinctness of L. pes, L. Tethyae, and L. Lepto- 
clini, all of which are provided with alate expansions of the 
foot, it is obvious that no sufficient diagnosis of L. alata has at 
present been given. 
The foot-gland has been described by Schmidt (11) as 
consisting of a round granular mass situated in the angle of 
the foot, and communicating with a duct which traverses the 
“ sole ” and opens at the free end of the foot by a small pore ; 
the duct is surrounded by four rows of large cells. In L. 
neapolitanum, Kowalewsky (3) states that the duct opens 
by a series of pores occurring in variable number along the whole 
of its course. In L. pes, L. Leptoclini, and L. Tethyae, 
my observations confirm neither of these statements ; and it is 
worthy of remark that in L. pes I have had occasion to 
