studies on marine Ostracods 431 



always large and well developed, the end joint of the endopodite is, on the other hand, com- 

 paratively small; the e x o p o d i t e is more or less strongly reduced, l>ut is always distinctly 

 developed. P r o t o p o d i t e : The endite of the coxale : This is always well developed both 

 in the male and the female. It is comparatively large, but it is certain, all the same, that it can. 

 not be used for mastication. It is bifurcated, but the two points are so close to each other that 

 at first sight it seems to be undivided. Its dorsal point is differentiated into a hyaline, rather 

 long, narrow, flexible and somewhat scythe-shaped process, which is compressed from the sides 

 like a lamella and is directed towards the mouth. Its ventral point is considerably shorter and 

 is rather narrow. The second protopodite joint is differentiated proximo-medio-ventrally 

 into a conical process, which is armed with bristles and points towards the mouth. The e x o- 

 p o d i t e has two bristles, situated ventero-distally, and in most cases very short. There 

 are always a large number of glands emerging on the exopodite. Endopodite: This is 

 always three- join ted, its end joint has a somewhat varying number of bristles. 



Maxilla: — This has no (or sometimes very slight?) sexual dimorphism. — It is of 

 a very strange type, differing greatly from all other Ostracods so far known; see fig. Ill: 4. 

 It is not developed as a masticatory organ. It is moderately large, but rather weak, with weak 

 chitinization and a rather weakly developed muscular system. It seems, like this limb in 

 Cypridinidae, to have had five joints originally, three protopodite and two endopodite joints, 

 but it has now only a slight indication of division into joints or even sometimes no division 

 at all. The three joints of the protopodite always seem to be quite united; the boundary between 

 the protopodite and the endopodite, like the boundary between the two endopodite joints, often 

 seems, on the contrary, to be more or less perceptible. — Protopodite: The procoxale 

 and the coxale are rather voluminous, but presumably rather short. The basale, which, like 

 the two preceding joints, is directed forward and somewhat outward, seems, on the other hand, 

 (contrary to what is the case in other known forms) to be comparatively long; it grows somewhat 

 narrow distally and is somewhat arched in two planes, partly downwards and partly — like the 

 procoxale and the coxale — inwards. On the procoxale and the coxale there are reduced endites, 

 which are certainly quite useless for breaking up food; there are no endites on the basale. Latero- 

 ventrally along the whole length of the protopodite there runs a rather strong chitinous list, 

 coming to an end posteriorly on the medial side of the limb just behind the proximal endite, 

 after having curved round the proximo-ventral part of the protopodite. From this list issues 

 a very dense series of homogeneous bristles pointing ventrally and situated close together — 

 almost like the plates of baleen of a baleen whale. These bristles are rather long and stiff, com- 

 paratively narrow and not annulated; they decrease fairly uniformly in length from front to 

 back. The posterior bristle in this series differs somewhat in type. The protopodite always 

 seems to have an e p i p o d i a 1 appendage dorsally. There never seems to be any trace of an 

 exopodite or else it is represented by a single bristle or a small group of bristles situated 

 distally-laterally -ventrally on the basale. The e n d o p o d i t e is rather short, in most cases 

 considerably shorter than the basale; it ])oints downwards and when at rest is almost at right 

 angles to the protopodite; it becomes narrow towards the point. The ilrst endopodite joint is 

 rather well developed, somewhat elongated; the end joint is, on {\w other hand, very short. 



