lO 



G. O. SARS. M.-N. Kl. 



the free edges of the valves are densely spinulose, and similar appressed 

 spinules also clothe the spine of the carapace, and are continued for some 

 distance along the dorsal edge, the anterior part of which, however, is 

 quite smooth. 



The head is of moderate size, and not distinctly defined dorsally from 

 the carapace, though the upper edge appears slightly concave in the 

 nuchal region. It has, along the middle, a very slight keel, which is the 

 immediate continuation of the dorsal crest of the carapace. Seen laterally 

 (fig. i), it slight!}^ tapers towards the front, without forming any gibbous 

 expansion dorsally, the dorsal margin being quite evenly curved, and con- 

 tinuous with the anterior edge. The latter joins the ventral edge by a 

 strong, but quite even curve, whereby a somewhat projecting rounded 

 frontal part is formed, within which the eye is located. The ventral edge 

 is very slightly concave, and terminates in a short, but acute, deflexed 

 rostral projection (see fig. 3), behind which is a rounded expansion car- 

 rying the antennulae. 



Seen from abo^-e (fig. 2), the carapace appears rather compressed, 

 its greatest width but little exceeding half the height. The head, in this 

 view of the animal, exhibits a somewhat triangular form, its anterior part 

 being somewhat narrowed, and terminating in a short point, whereas its 

 posterior part appears rather broad, owing to the prominent fornix. The 

 latter joins the carapace, without forming any projecting corner. 



The eye (see figs, i, 2, 3) is comparatively large, with distinctly 

 projecting crystalline bodies. The ocellus, on the other hand, is extremely 

 minute, punctiform, and, as usual, located at some distance behind the eye, 

 at the lower corner of the cerebral ganglion (see fig. 3). 



The antennulæ (ibid) are distinctly projecting, though, as usual in the 

 female sex, small and quite immobile, being tipped by the usual fascicle 

 of olfactory papillae. 



The antennæ (see fig. i) are of moderate size and quite normal in 

 structure. 



The tail exhibits the usual dorsal lappets, which, however, are less 

 strongly developed than in D. dolichocephala. The 2 lower ones are 

 well defined, though confluent at the base. The terminal part (fig. 4) is 

 somewhat narrowed distally, and is armctl on each side of the anal fissure 

 with from 12 to 14 denticles of nearly equal size. The terminal claws 

 (see fig. 5) are of moderate length, and exhibit at the base a dense series 

 of slender spinules. Between these claws and the outmost of the anal 

 denticles, a small sinus is formed. 



