32 
orifices are shown only in some of the illustrations of the genital region, and they are 
often very difficult to find, if one or each of them has not a spermatophore attached to it; 
this, however, is rather frequently the case; sometimes we find even two spermatophores, or 
at least their stalks, on each orifice (pl. XITI, fig. 1e). Such a spermatophore is a globular 
or ovate vesicle with a stalk twice or three times as long as itself; this stalk — a thin 
tube — is attached to the skin closing on the above-mentioned orifice, or sometimes — by 
mistake — outside it (pl. LV, fig. 2c, where we find one spermatophore on each orifice and 
the stalk of a third one outside it). The two receptacula, when filled, have a strong 
refraction of light, which as a rule makes them easy to find. Their outlines are traced with 
dotted lines in some of the illustrations. — In Spher. Munnopsidis I have found in the an- 
terior part of the plate two holes (pl. X, fig. 4c, k) corresponding to those in Mysidion 
abyssorum and Aspidoecia (see p. 34—35). 
In the species which have trunk-legs there is always a pair of caudal stylets shaped 
somewhat like the legs. Jn Homocoscelis (pl. 11 and pl. XIII) they are a little thicker and 
longer than the legs; in Spheronella and Choniostoma they consist either of a cylindrical, a 
rounded or a triangular joint terminating in two or three sete (which rather frequently fall 
off during the preparation): they are sometimes longer, sometimes shorter than the sete of 
the legs (as e.g. pl. VII, fig. 2e). In Spheronella Acanthozonis each caudal stylet has one 
single rather long seta (pl. VII, fig. 5d). In Spher. modesta, which has no trunk-legs, each 
stylet consists of a rather short, thick joint, from the inner posterior angle of which proceeds 
an acute »joint« twice as long but scarcely half as thick, which must be considered as a trans- 
formed seta, and outside it are seen one or two simple setze (pl. LX, fig. 2e). Nearly all the 
other species which lack trunk-legs are devoid of caudal stylets as well. The place of these 
stylets varies much; in most species they are situated close together, either on the plate or 
the ring, a little behind the genital apertures, or close behind the posterior margin of the 
ring or plate, but in the species belonging to the group of Spheronella Leuckartii they are 
situated pretty far or very far from each other, and also more or less far behind the genital 
area (pl. II, fig. 2e and fig. 3b). 
The remarkable fixation of Spheronella paradoxa will be described in the systematic 
part; here it may be sufficient to draw attention to it. 
II. Stenothocheres (pl. I). This genus, comprising two species, deviates considerably from 
the three recently mentioned genera, and in at least two important features: — larger trunk-legs 
with two branches and a separate abdomen — it comes nearer to the less transformed Copepoda. 
The body is sub-ovate or nearly globular; its abdomen is comparatively rather small 
and prominent posteriorly on the ventral side or on the hind margin itself. It has no separate 
head, not even the vestige of a frame (like the one in Choniostoma). The sub-median skeleton 
is reduced to a plate in front of each maxilliped (pl. I, fig. 1e,h and fig. 2f), and this plate 
may extend forward like a list between the maxilla and the outside of the rostrum.  An- 
tennule, antenne, rostrum, maxilla and maxillipeds occupy a larger space on the ventral 
