^IioumJi/Ma^^^^^^^ J^otjal MicToscopical Society, 271 
no more alteration than could be accounted for by the action of the 
preservative. 
H iving fully described the zoosperms in four species of Crus- 
tacea, we now come to the consideration of the vessels destined to 
convey them into the spermatheca of the female, viz. the sperma- 
tophora, these are precisely alike in G. Mmnas, M. verrucosa, and 
S. Longirostris, so that the description of one will equally apply to 
the others ; in all these species (Fig.- 5) they consist of a spherical 
body, whose walls are formed of a fine and transparent membrane, 
not divisible into more than one layer, and consisting apparently of 
chitine ; they occur of all sizes, ranging from that of the figure 
down to some only just large enough to contain three or four 
zoosperms ; others are empty : the larger ones are generally full of 
zoosperms, so crowded together that the outlines of the latter are 
indistinguishable. 
The lobster does not possess any proper spermatophorum ; the 
zoosperms having arrived at the vas deferens are found imbedded 
in an extremely viscous and granular substance, which fills up the 
whole tube. 
In P. Bernhardus (Fig. 6) the spermatophora consist of two 
distinct parts, a basal portion, flat and oblong, and the spermato- 
phorum proper; the basal portion is formed of a material which it 
is difficult to tear asunder with needles, being of a tenacious and 
rather elastic nature; numerous granules are dispersed over the 
surface, the larger ones being collected near the edges ; transversely 
across the middle line are sometimes seen large spaces or holes, 
indicating the former separation of the base into distinct sections ; 
v/here the holes do not exist, their place is occupied by a faint line, 
the intervals between them are occupied by the spermatophora 
proper, which arise by root like processes from the central line of 
the bases, and project at right angles ; their number varies from 
one to seven, they are of an elongated lanceolate shape, their 
structure is as follows : from the root-like processes arises a solid 
rod, which soon divides into two thick branches in a forked manner, 
these becoming thinner run up on each side to the apex where they 
join, thus forming the framework of the spermatophorum ; the in- 
terval is occupied by a fine hyaline membrane, enclosing the cavity 
of the spermatophorum, which is densely filled with zoosperms, but 
leaving an empty space towards the root ; there is almost always a 
small cavity in the wall, where the framework becomes thinner, 
contaming a few zoosperms which seem to have become separated 
from the general mass; in one specimen that I examined, this 
collection occupied a projection in the form of a hook-like process 
of the wall. When the spermatophora are squeezed, the zoosperms 
are seen to emerge from the apex, where the framework is thicker 
but softer than the remainder; the opening closes again by the 
