8 G. 0. Sårs. 



protuberance below, containing the genital orifice. To this 

 protuberance the large flattened ovisac is attached, and also, 

 not infrequently, a varying number of spermatophores, pro- 

 jecting to one side or the other (see fig. 1). The second 

 segment is a little longer than the 1st, and gradually widens 

 somewhat distally. It exhibits at some distance from the tip, 

 dorsally, a projecting transverse fold, behind which the anal 

 orifice occurs, bounded by a soft-skinned area. The caudal 

 rami, or furca, are of moderate size, slightly exceeding half 

 the length of the last segment, and are about twice as long 

 as they are broad. They are but slightly divergent, and 

 have the inner edge straight and densely ciliated, whereas 

 the outer edge appears somewhat curved. The caudal setæ 

 on each ramus are 5 in number, 3 of them issuing from 

 distinct ledges on the outer edge, the other 2 from the tip. 

 Of the setæ, the innermost is the smallest; the other 4 are 

 about equal-sized, and somewhat exceed the ramus in length. 

 They are all very densely ciliated, and form, together Avith 

 the rami, a broad fan constituting a very effective propulsive 

 apparatus. As in most other Diaptomids, a very slender, 

 unciliated bristle, moreover, occurs on each ramus, originating 

 from the dorsal face near the tip, and generally extending 

 between the 2 innermost caudal setæ. 



The anterior antennæ (see figs. 1 and 2) are about the 

 length of the anterior division of the body, and are rather 

 slender, gradually tapering distally. They are described by 

 Loven as being composed of 27 articulations, but this is 

 evidently due to a miscomprehension; for in no other known 

 Calanoid has so large a number of articulations ever been 

 observed. On a closer examination, it is indeed easily 

 proved that the number of articulations is that usually found 

 in the Diaptomidæ, as also in most other Calanoids, viz., 25. 



