studies oil marine Ostracods G79 



first joint and the total length of the eight following joints is about 10 : 4. The proportion 

 between the length of the longest natatory bristles and that of the exopodite is about 7 : 5. 

 The first joint is similar to that of C. symmetrica. E n d o p o d i t e: This has two joints. First 

 joint: The a- and b-bristles have short hairs, almost bare. Second joint (fig. 4): The proportion 

 between the length of the g-bristle and that of the protopodite is about 3:4; this bristle has no 

 distinct shaft and is rather broadly sword-shaped distally (cf. the accompanying hg. 5). The 

 f-, h-, i- and j-bristles are subequal and about a quarter or a fifth shorter than the g-bristle; 

 they all have rather well developed shafts and are not sword-shaped distally. The g-, f-, h-, 

 i- and j-bristles have short hairs proximally; the four latter ones are quite or almost quite bare 

 distally; the g-bristle has short hairs along one edge. There are no c- and d-bristles. Between 

 the h- and i-bristles there is an exceedingly small papilla. Pilosity: The second endopodite 

 joint is bare. 



Mandible: — Protopodite: The toothed edge of the pars incisiva is of a type 

 rather different from the rest of this genus (see the accompanying fig. 6). Its anterior tooth 

 is of about the same type and relative size as in (all?) the other species of this genus. Behind 

 this tooth there follows a series of (somewhat more than twenty) smooth triangular teeth, of 

 which the anterior ones (about five) are moderately large and strong, the others decreasing in 

 size and strength the more posteriorly they are situated; the posterior ones form a fine serrulation. 

 This edge ends posteriorly with a powerful, low, wide, irregularly rounded, smooth tooth. Distal 

 tooth-list (see the accompanying fig. 7): This is somewhat narrower than the toothed edge; 

 it has a large, powerful, smooth, fang-like posterior tooth and a single row of about fifteen to 

 seventeen simple, smooth, pointed, moderately large teeth which vary somewhat in size. Prox- 

 imal tooth-list (see the accompanying fig. 8) : This is somewhat narrower than the distal tooth- 

 list. It has a relatively small and somewhat varying number of smooth, pointed teeth, of which 

 the posterior one is of about the same type and strength as the posterior tooth on the distal 

 tooth-list, the others decreasing irregularly in size and strength, the anterior ones being quite 

 small (on both the mandibles in the specimen investigated they were about the same type as 

 in the accompanying figure). The masticatory pad is rather high, divided into four- thin plates 

 placed transversaUy, the distal one of which is somewhat narrower than the proximal tooth- 

 list, the others decreasing somewhat in width the more proximally they are situated; the free 

 edges of these plates are deeply and irregularly toothed (cf. the accompanying fig. 9). The part 

 of the pars incisiva that is surrounded by lancet-bristles and hairs is somewhat raised and is 

 furnished with dense papillae and short, fine hairs. Basale: This has the same number of teeth 

 on the distal edge of the endite as in the other species of this genus investigated by me; the 

 difference between main teeth and secondary teeth has, however, almost vanished (the former 

 are considerably weaker, the latter considerably stronger, than in the majority of the species 

 of this genus), so that this edge seems rather finely and evenly serrulated (cf. the accompanying 

 fig. 10). The single tooth on the outside of this process is somewhat wider than each of the (six) 

 distal teeth and is quite or almost cj^uite smooth. The two appendages on the posterior edge 

 of this endite are furnished with unusually strong secondary spines. Tlie disto-medial bristle 

 on this joint is relatively long and has long hairs. The epipodial appendage is 



