239 



Gen. 4. ClypeOnlSCUS, Giard & Bonnier. 1895. 



Generic Characters. Body of adult female forming a somewhat flattened 

 bag of oval form, without any distinct segmentation, but with the lateral parts 

 slightly lobular, and both extremities briefly incised ; dorsal face convex and exhi- 

 biting somewhat in front of the middle an opaque area, ventral flattened, with a 

 longitudinal slit leading to the inner cavity, and admitting of being closed by a 

 number of small valvular lamellae defining it on each side. Within the bottom of 

 the posterior incision an extremely small projection occurs, constituting the hind 

 extremity of the animal. No distinct affixing apparatus present. - - Male compara- 

 tively short and thick, with the basal expansion of the antennulse very broad and 

 densely pectinate. Coxal plates likewise distinctly pectinate. Antennae comparatively 

 short. Uropoda with the outer ramus much smaller than the inner. 1st larval 

 stage distinguished by the presence of a broad operculiform plate covering the 

 ventral face of the tail. Parasitic in the marsupial cavity of Isopoda belonging to 

 the family Idotheidce. 



Remarks, This genus, recently established by MM. Giard and Bonnier, 

 is well distinguished from the other Cryptoniscian genera by the flattened cake- 

 like shape of the adult female, as also by the peculiar shield-like plate occurring 

 in the 1st larval stage beneath the tail. It is, indeed, the latter character which 

 has given rise to the generic name proposed by the said authors. They record 

 2 different species, the distinctness of which, however, appears to me somewhat 

 questionable, although they are from widely distant localities and have been found 

 on different species. 



ClypeoniSGUS Hanseni, Giard and Bonnier. 



(PL XCIX, fig. 1). 



Clypeonlscus Hanseni, Giard and Bonnier, Contributions a 1'etude des Epicarides, in Bulletin 

 scientifique de la France, T. XXV, p. 444, PI. VII X. 



Specific Characters. Body of adult female oval quadrangular in outline, 

 with both extremities nearly alike, or the anterior very little narrower than the 

 posterior, lateral parts divided into 5 6 rounded lobes, which, however, often 

 appear less regular and sometimes are almost obsolete ; dorsal opaque area not 

 very distinctly defined, and oval in form ; caudal prominence very small, clavi- 

 forrn, briefly bilobe^d at the tip. - Male oval pyriform in outline, but little more 

 than 3 times as long as it is broad; cephalic segment evenly curved in front; 



