1909-] N. Annandai^e : The Indian Cirnpedia Pedunculafa. m 



deep purple in very large specimens, often with the outlines of the five primitive 

 valves well marked upon it ; the calcified valves covering about half the surface but 

 widely separated from one another, more or less fully calcified, translucent or opaque. 

 Ter gum shaped Hke an axe or a horse's head and neck, the handle of the axe (or neck 

 of the horse) stout, slanting downwards towards the scutal margin of the carina, 

 which it does not nearly reach ; a considerable vertical depression usually present on 

 the anterior part of the valve. Carina extending upwards far above the carinal angle 

 of the tergum, usually rather broad, with a broad irregular dorsal ridge on the basal 

 third or quarter, split transversely into two plates (the upper of which is devoid of a 

 special centre of calcification) through this ridge; the basal branch well-developed, 

 running parallel to and below the basal margin of the scutum, deeply buried, ter- 

 minating in a large, broad, oval, flat transverse disk, the lateral margins of which 

 usually bear conspicuous ridges ; the edge of the disk more or less notched and irre- 

 gular, as the whole margin of the lower part of the valve also frequently is. Scutum 

 with two branches or segments, the separation being incomplete in some speci- 

 mens ; the occludent margin nearly straight, cone-shaped, slanting outwards from 

 above, its apex separated from the scutal margin of the tergum but corresponding 

 with the deep excavation therein ; carinal segment much shorter than the occludent 

 subtriangular, the upper angle usually being rounded and the carinal margin more or 

 less concave. 



PEDUNCI.E cylindrical or compressed, usually smooth, tapering towards the base, 

 moderately stout, naked or with minute chitinous points. 



Cirri, etc. — First pair of cirri, in the natural position, not far removed from 

 second, but remote if the animal be stretched out, from ^ to f as long; the anterior 

 ramus slightly shorter than the posterior, but of the same width; each ramus with six 

 distinct joints, which are sub rectangular towards the base and oval near the apex ; 

 each joint well encircled by bristles. Second cirrus with the anterior ramus slightly 

 shorter than the posterior, its bristles (as those of the cirri posterior to it) well 

 developed but more slender than those on the first cirrus ; the anterior margin of the 

 segments distinctly convex, while in the third to sixth cirri it is almost straight, pro- 

 jecting outwards at the apex of the segment and slanting in towards the base. The 

 cirri as a whole rather feebly curved. Anal appendages slender, rounded at the tip 

 (which usually bears a bunch of long hairs), very variable in length, curving outwards 

 from the base. Penis of moderate length, rather slender, tapering, covered with scat- 

 tered hairs and more or less distinctly annulated, bearing at the tip a bunch of less 

 sparse hairs and a delicate process, which is apparently retractile. 



Mouth parts. — Lahrum buUate, with a row of comparatively large teeth. Palp 

 short and stout, with long hairs at the tip. Mandible with four or five teeth, the 

 fifth being small and blunt when present. Maxilla with a deep incisure, closely 

 resembling the maxilla of D. bathynomi. 



The capitulum occasionally reaches a length of at least 11 '5 mm. 



This is another variable species, probably recognized as such only owing to the 

 fact that large numbers of specimens have been examined. It is by far the commonest 



