FAMILY TIES o6l 
groups. ‘The specific name refers to the serrate margin of 
the movable branch of the uropods. Sphceroma curtum, 
Leach, is common among seaweeds on the coast of Devon, 
but isolated rather than in groups. Spheroma Prideaux- 
zanum, Leach, may be regarded as a synonym of the pre- 
ceding, founded on large specimens. Sphceroma rugicauda, 
Leach, is distributed over the coasts of England, Scotland, 
and Ireland, frequently where the water is not very 
saline, as, for instance, at Barnstaple in North Devon. 
The stilets of the second pleopods in the male are very 
elongate, apically widened and rounded. Sphceroma 
Hookeri, Leach, is very similar to the preceding species, 
but distinguished by two small longitudinal ridges on the 
pleon. Both species have been taken in company on the 
coast of Sussex. 
Zuzara, Leach, 1818, was established for species differ- 
ing from Spheroma by having the outer branch of the 
uropods larger than the fixed inner one, and concave above 
instead of flat. ‘The species also have the sixth segment 
of the perzeon dorsally produced. 
Neesa, Leach, 1818 (Nesea, Leach, 1814, preoccupied), 
has the sixth segment of the perzeon larger than the others, 
and produced backwards in a bidentate process. The uro- 
pods are affixed not at the base, but near the further end, 
of the terminal segment, and, while the fixed inner branch 
is directed transversely inward, the movable outer one ex- 
tends backwards beyond the end of the segment. In the 
British species Nesa bidentata (Adams), the pleon is rugose 
with two dorsal tubercles and a terminal excavation. Bate 
and Westwood suggest that this species may prove to be 
the male of Dynamene Montagu, Leach, in which there 
are two dorsal tubercles on the sixth segment of the pereeon 
and two on the pleon. It seems not improbable that the 
species named Dynamene rubra and Dynamene viridis by 
Leach, and Campecopea versicolor by Rathke, may repre- 
sent the female, and Dynamene Montagui the young male, 
of Neesa bidentata. These forms are all found on British 
coasts under similar conditions and with the same varia- 
tions of colour—green, or red, or variously mottled; but 
