91 



lenght, dorsal margin boldly arched, without any abrupt bend, ventral margin 

 scarcely at all sinuated, anterior extremity obliquely rounded, posterior rather 

 broader and obtusely blunted; seen dorsally, broadly ovate in outline, with 

 the greatest width somewhat behind the middle and about equal to the height, 

 anterior extremity obtusely pointed, posterior rounded off. Surface of valves 

 smooth and clothed with short hairs more conspicuous at each extremity, 

 hyaline borders in front and behind rather slight. Anterior antennae with the 

 terminal part about the length of the basal one, and having the joints gradually 

 diminished in size, last joint very small, setae much elongated and distinctly 

 ciliated. Posterior antennae with the penultimate joint scarcely more than half 

 as long as the preceding joint; apical claws very slender and almost straight. 

 Posterior legs with the terminai joint considerably exceeding half the length 

 of the penultimate one, shortest apical seta comparatively small. Caudal rami 

 considerably produced and perfectly straight, with the dorsal edge in its greater 

 extent fringed with minute spinules, apical claws remarkably short and stout, 

 the distal one scarcely exceeding l ji of the length of the ramus. 



Male, as a rule, slightly larger than female, but scarcely differing from 

 it in the shape of the shell. Prehensile palps of maxillipeds rather dissimilar, 

 the right one having the propodos slightly narrowed distally, and the dactylus 

 remarkably broad, sublamellar, and almost angularly curved; left palp with the 

 propodos somewhat broader and exhibiting near the end inside a dentiform 

 prominence, dactylus narrow falciform. Copulative appendages comparatively 

 large, terminating in a broadly rounded lobe. Ejaculatory tubes remarkably 

 short and massive, with the whorls of radiating spikes densely crowded and 

 somewhat obliquely disposed in relation to the central duct. 



Colour bright yellowish brown, somewhat darker in male than in female. 



Length of adult female amounting to 0.88 mm. 



Remarks. This form was recorded as early as the year 1863 by the 

 present author, but was not described in detail or figured. Yet, it has been 

 well recognised by most subsequent authors, its comparatively large size 

 rendering it indeed readily distinguishable from any of the other known species. 

 The form recorded by Brady in his Monograph under the name of Cypris 

 cinerea is evidently identica with the present species, the figures given having 

 apparently been drawn from an immature specimen. G. W. Muller has proposed 

 to change the specific name globosa to dispersa, but I do not find that such 

 a change is required.. 



Occurrence. I have taken this form in several places around Christiania 

 in small pools and ditshes liable to exsiccation during the summer. It is a 



