262 
SIDNEY F. HARMER. 
restricted to two, as supposed by Schmidt ; they are formed 
alternately on the two sides of the body, as in L. Kefer- 
steinii (10), and a young bud usually occurs at the base of 
every nearly mature bud, in addition to a third on the opposite 
side, intermediate in age between the two just mentioned. 
The stalk in most cases is at least twice as long as the calyx, 
and is provided with a well-developed foot-gland with lateral 
wing-like expansions. Round the free edge of the calyx, as 
seen when the tentacles are retracted, is a definite series of 
gland-cells described by Salensky (15). The ectoderm of the 
stalk is arranged as eight longitudinal rows of cells (PI. XIX, 
fig. 9), and this is not the case in any of the other species 
investigated. 
Habitat, on the sponge Tethya. 
2. L. pes, Schmidt (originally described by Schmidt as L. 
singulare). — The tentacles are thick and short, and were ten 
in number in all the individuals examined. In no case 
observed was either side of the body provided with more than 
a single bud. The stalk is usually considerably shorter than 
the calyx ; the foot-gland is very large, and the foot is pro- 
vided with well-developed alate expansions. The character- 
istic gland-cells of L. Tethyse are not present, and the 
ectodermic cells of the stalk are arranged irregularly. The 
larva (Schmidt, No. 11, Taf. ii, fig. 25) resembles that of L. 
Tethyse. 
Found in small numbers on Euspongia and Caco- 
spongia. 
3. L. singulare, Keferstein. — This species was found on 
the ventral side of Aphrodite (as described by Barrois), and 
of Hermione hystrix. The identification is somewhat 
doubtful, Keferstein's individuals possessing ten tentacles, 
whereas in the Naples species the number is larger, and in the 
very few specimens obtained appeared to be twelve or thirteen. 
The stalk, terminating in a slightly expanded disc, as in the 
form described by Keferstein (2), is very short and is much less 
distinctly marked off from the calyx than in the other species, 
the whole animal being somewhat pear-shaped. None of the 
