REPORT ON THE OSTRACODA. 167 



The range of tliis species appears to be almost exactly identical with that of Ilalo- 

 cypris atlantica, but it is perhaps not quite so abundant, many of the bottles in which 

 the latter species occurred being destitute of Halocypris hrevirostris. The almost entire 

 absence of striation, and the subgiobose contour of this species, suffice to distinguish it 

 at once from Halocypris atlantica. 



[PI. XXXIX. figs. 1-11. 1 Carapace of female seen from left side, 2 the same seen from 

 above, 3 seen from front, 4 carapace of male seen from left side, 5 seen from above, 6 anterior 

 antenna of male and female, 7 secondary branch of posterior female antenna, 8 secondary 

 branch of posterior antenna of male, 9 mandible and palp, 10 foot of first pair of female, 

 11 one lamina of postabdomen. Figs. 1-5, magnified 25 diameters.] It should be 

 noted that the front view of the shell given in figure 3 is, through an oversight, not 

 shown in the customary position, the ventral (narrow) edge being placed upwards. 



3. Halocypris imbricata, n. sp. (PL XLI. figs. 1-10, and PI. XLII. figs. 1-8). 



Shell compressed, elongated, lower in front than behind, and produced in front into 

 one very long, curved, slender rostrum (PL XLII. figs. 1, 2), the dorsal margin also 

 extended into a long spine, which is directed straight backwards, the spine being double, 

 the half belonging to the left valve much smaller than that of the right ; the hinder 

 ventral angle of each valve is likewise produced into a wide, sharply -pointed triangular 

 appendage, directed nearly straight backwards ; the anterior angles are rounded ofi", but 

 are fringed with minute teeth, which are arranged in several successive series (fig. 3), 

 each series composed of four or five teeth, increasing regularly in length from the first to 

 the last. Seen from the side, the anterior extremity of the shell is narrowed and rounded, 

 the long, slender rostrum projecting, however, very far beyond it ; the dorsal margin is 

 deeply indented in the middle, slightly convex in front, and a little sinuated towards the 

 posterior extremity ; the posterior extremity is produced dorsally into a long spine, below 

 which it is nearly straight, the ventral angle being rounded ofi", except when it is 

 encroached upon by the pair of triangular spines ; ventral margin nearly straight ; the 

 texture of the shell is reticulated, the reticulations being arranged in more or less regular 

 transverse rows over a considerable portion of the valves, but a longitudinal striation, 

 especially towards the margins, being also distinctly apparent ; in the ventral spinous 

 processes, as well as near the margins of other parts of the shell the areolas are dis- 

 tinctly imbricated, and might fairly be called scales (fig. 4). The anterior antennae of 

 the female (PL XLI. fig. 1) has four very short granulated appendages, and one long, 

 annulose setae ; in the male (fig. 2) there are two short club-shaped appendages and three 

 long annulose setae, one of which (fig. 2, a) bears on its central portion a fringing armature 

 of about forty closely-set delicate hair-Hke spines arranged in a pectinate manner, the 

 whole series beginning and ending quite abruptly. The secondary branch of the posterior 

 antenna in the female (PL XLII. fig. 5) has two long and two short ringed setse ; in the 



