studies on marine Ostracods IVl^l 



their length tliey have a single, large, powerful suctorial disc. The c-, f- and g-bristles are consi- 

 derably longer in tlie male than in the female; the b-bristle but slightly lengthened in the former. 

 Second antenna: — The protopodite has a medial-distal bristle. 

 E X o p () d i t e: The bristle of the second joint rather powerfully developed, unarmed. The 

 natatory bristles on the third to ninth joints entirely without spines. The last-mentioned joints 

 with or without basal spines. The endopodite developed in the males into a powerful 

 clasping organ with three joints. Besides the proximal-ventral bristle its end-joint has two 

 short distal bristles placed close together. In the females the endopodite is also comparatively 

 well developed, extended, with three joints; the bristle of its end joint very long. 



Mandible: — Protopodite: The endite of the coxale is weakly bifurcated 

 (listallv; some of its spines are rather powerful, those on the medial and also some of those on 

 the lateral side arranged in very distinct groups. Apart from the bristle of the endite there 

 are no bristles on the coxale joint. Basale: Of the ventral bristles one d-bristle is very long, 

 furnished with numerous long secondary bristles and short-haired distally; the rest of these 

 bristles are of moderate length or short, most of them furnished only with short hairs. On 

 the dorsal side tltis joint has three bristles. Endopodite: The first joint has four bristles 

 ventrallv. The anterior side of the second joint is very richly furnished with bristles. The 

 end joint armed with seven bristles, of which the medial of the two middle ones is longer than 

 the others and claw-shaped. 



Maxilla: — Protopodite: The coxale has dorso-distally a single long- fine- 

 haired bristle. Proximally on the outside of the third masticatory process there is a single 

 bristle. At the boundary between the basale and the first endopodite joint there are in most 

 cases three bristles, one close to the exopodite, one at about the middle of the inside of the 

 endopodite and one at the anterior margin of the latter. The coxale has dorso-distally a rather 

 large, leaf-shaped epipodial appendage. The exopodite is comparatively well 

 developed, with thick, long fine hairs; not displaced distally. The endopodite is broad 

 and moderately long. 



Sixth limb: — The second exopodite joint rather short; somewhat rounded, 

 and furnished with numerous bristles; the posterior-distal ones of the latter do not dominate 

 the others at all strikingly. 



Seventh limb: — Fitted with very numerous cleaning bristles; a large number 

 of these are placed close together near the point of the limb, the rest spread irregularly along 

 the distal part of the limb; as to the position of the last-mentioned bristles it is to be noticed 

 that most often there is only one bristle on the same side of one and the same joint, two 

 bristles are, however, not infrequently found close to each other on the same joint. The end 

 comb consists of a very large number of teeth of moderate strength, all of about the same type 

 and size. Dorsally close to the end comb the wall of this limb is not at all or only slightly 

 thickened, forming merely a slight depression. There is no special muscle for compressing 

 the latter. 



Furca: — ■ The lamellae are short. The number of claws is about 10—1.5, without 

 any clear division into main and secondary claws. 



