studies on marine Ostracods 



473 



The fourth to the ninth joints of this branch each have a basal spine. The endopodite 

 is distinctly three-jointed; its distal bristle is slightly longer than the stem. 



Mandible: — Protopodite: Coxale: The scythe-shaped process (figs. 8,9): 

 The part distally of the main spine narrows uniformly and gently into a fine point; its ventral 

 edge is even and rather decidedly convex. The distance from the point of the process to the 

 main spine is about as long as or somewhat longer than the distance from the latter to the 

 proximal ventral spine. The dorsal bristle is fixed at about a similar distance from the point 

 of the process as from the main spine and at a distance of about its own length distally of the 

 latter; it extends only slightly distally of the point of the process. The dorsal serrate teeth are 

 very weak; some are scarcely developed. The main spine is moderately strong. There are 

 six ventral spines; of these the three proximal ones are rather strong, the distal ones sometimes 

 rather weak; the distal one, or sometimes the two distal ones, is pointed proximally. On the 

 part distally of the main spine there are seven or eight transverse rows of hairs. The rod-shaped 

 process has three or four short, strong distal spines. Basale : The backward pointing process 

 has four end bristles, three or four triaena bristles and two dwarf bristles. The triaena bristles 

 have from three to fifteen pairs of secondary spines under the main pair of spines. The glands 

 emerge on a rather weakly developed papilla (this papilla is weaker than in fig. 9 of A. spinifera). 

 Dorsally at about the middle this joint has five rather short bristles, subequal or of somewhat 

 different lengths, equipped on the anterior side with short, fine hairs (the species has 

 derived its name from this character); close to these bristles there are groups of short, fine, 

 stiff hairs (fig. 7). The e x o p o d i t e is, if its two end bristles are included, about as long 

 as or rather slightly shorter than half the length of the anterior side of the first endopodite joint 

 (fig. 7). Endopodite (figs. 7 and 10): Of the three ventral bristles on the first joint the 

 shortest has short, fine hairs, the two others are furnished with short secondary bristles proxi- 

 mally of the long secondary bristles; on one bristle about ten to fifteen, on the other about 

 twenty to thirty pairs of similar short secondary bristles were observed. This joint is not armed 

 with spines antero-distally. The second joint has two proximal bristles of somewhat different 

 lengths; the longest is somewhat less than half the length of the main bristle a. Between the 

 main bristles b and c there is a long narrow bristle with short hairs. The medial cleaning bristles 

 are rather numerous and are arranged in two rather steeply descending rows. They vary to 

 some extent; three specimens that were investigated showed the following conditions: 



Type specimen: Right mandible 



f) bristles in a distinct lower row. 



i ,, ., ,, ., upper „ 



1 bristle above bristle no. 2 of the latter row. 



Sp 



Left 



ecimen no. 2. Right 



(! 



6 bristles in a distinct lower row. 



I » „ „ „ „ upper ,, 



\ 1 bristle above bristle no. 2 of the latter row. 



I 



6 bristles in a distinct lower row. 

 5 



I ^ ., „ „ upper „ 



I 1 bristle above bristle no. 2 in the latter row. 



Zoolog. bidrag, Uppsala. Suiipl.-Bil. J. 



50 



