10 TAGE SKOGSBERG, A NEW FRESH-WATER OSTRACOD. 
Cyprinotus gregarius n. sp. 
Cuprinotus dentato-marginatus -q O.; SARs,. 1889, p.. 6; Pl. I, figs, 1—4; Pl. III sfigs. 1— 11501, IV: 
NNE MÖLLER, TOV2p. GA 
Description. — G. O. SARS, loc. cit. 
Male: Shell: Length 0;,8:—1 mm; length : height about 1,66: 1; length: 
breadth about 2,57 : 1. Surface irregularly reticulated (see the drawing). Hyaline 
border (»der Saum>) of the anterior extremity of both valves extending beyond the 
edge of the valve, that of the left valve distinetly broader than that of the right 
one. Hepatic appendage of the intestine does not extend farther than to the ante- 
rior margin of the testes, in other words to a point a little behind the middle of 
the valve. 
First antenna: seven-articulated, first and second original joints being almost 
perfectly joined; the number of the bristles agrees with that given by CO. CLAUS, 
1893, p. 23, as characteristic of the Cyprids examined by him, consequently not 
with that given by A. KAUFMANN, 1900, p. 223. First joint: somewhat in front of 
the middle a short-haired dorsal bristle of moderate length and ventero-laterally close 
to the distal end of the joint two long sete of about equal length are to be found; 
the proximal third of these two set&e naked, flattened and hyaline, strengthened 
only along its posterior edge, the distal two-thirds much narrower, finely, shortly, 
and densely feathered. Second joint only with a rather short, short-haired dorso-distal 
bristle. Third joint distally with a dorsal and a ventral short-haired bristle of mode- 
rate length, the ventral one a little shorter than the dorsal. Fourth joint with two 
very iong medial dorso-distal natatory bristles, like all the »natatory» bristles of this 
limb dorsally carrying rather long fine hairs, and two ventero-distal short-haired 
bristles, the ventral of which is about as long as or a little shorter or longer than 
the total length of the three distal joints, the other, originating medially, is about 
as long as or somewhat longer than the total length of the four distal joints. Fifth 
joint also distally with two long dorso-medial natatory set&e and two ventral bristles of 
moderate length; the upper, medial, of the latter, furnished with a few rather long 
fine hairs or almost naked, is about the total length of the five distal joints; 
the ventral is short-haired and somewhat shorter. Sixth joint: along the medial distal 
edge with four long natatory bristles and dorso-laterally with a short-haired bristle 
only about twice as long as the end-joint or even somewhat shorter. End-joint: 
with four distal setx; the dorsal, the sensorial one, not joined at the base to its 
neighbouring seta, about twice the length of this joint or a little shorter; the two 
middle ones are long natatory setze, and the ventral one which is short-haired is about 
the total length of the four distal joints. The longest natatory set of this antenna 
are somewhat longer than all the joints taken together. The four distal joints have 
distally short stiff hairs and on the inner side of the first joint somewhat ventero- 
distally to the middle a bunch of such hairs is generally to be found. The chitinous 
