ENTOMOSTRACA OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 579 
Tribe CALIGOIDA. 
Genus Dysgamus, Steenstrup & Liitken, 1861. 
Dysgamus atlanticus, Steenstrup & Liitken. (Pl. XIII. fig. 13.) 
1861, Dysgamus atlanticus, Steenstrup & Liitken, Bidrag til Kundskab om det aabne Havs Snyltelreb 
og Lernzer, p. 368, Tab. iv. fig. 8. 
Only the males of Dysgamus have apparently been observed hitherto, and it is 
doubtful if the genus can be considered a valid one till females are obtained. 
The specimens on which the genus was founded were taken, probably while 
WEES 
KES 
MU 
SWIG 
Fic. 1.—Foot of first pair. Fic. 2.—Foot of second pair. 
K jm 
ses p- 5. 
Fic. 3.—Foot of fourth pair. Fic. 4,—Abdomen and fifth pair of feet. 
Dysgamus atlanticus, Steenstrup & Liitken. 
swimming freely at the surface, at several places in the North Atlantic, between lat. 8° 
and 28° N., and long. 21° and 36° W. 
This species has a close resemblance to Caligus in its general form and colour; the 
frontal plates are, however, without Junules or sucker-disks. The carapace is broadly 
ovate and depressed, but the last two thoracic as well as the abdominal segments are 
short and comparatively narrow. The first four pairs of thoracic legs are all two- 
branched, and the branches two-jointed ; the first pair has the inner branch very small, 
but in the other three pairs the branches are subequal ; there is, as in Calzqus, a fifth pair, 
very minute but quite distinct (see text-figures annexed). The eyes, though visible, are 
not very conspicuous. The Scotia specimens were collected in the Atlantic at the 
