45 



by G. W. Muller by the reception within it of the family Cytherellidce. As 

 above shown, this family cannot however by any means find its place within 

 the present suborder. The name, as here given, alludes to the pronouncedly 

 pediform structure of the posterior antennae, the general appearance of which 

 is not unlike that of the mandibular palps in the Myodocopa. As to the shell, 

 the peculiar closure of the valves in the oral region is very characteristic, no 

 trace of such a closure being found in any of the forms belonging to the 3 

 preceding suborders, whereas in all the known Podocopa its existence may 

 easily be demonstrated. 



The present suborder comprises the far greater bulk of the known 

 Ostracoda, and is represented both in the sea and in fresh water. We may 

 distinguish within it 2 well defined families, viz., the Cypridce and the Cytheridce, 

 both established as early as the year 1852 by Baird and founded on the 2 old 

 genera Cypris and Cythere. True, in recent times several other families have 

 been added; but in my opinion these new families only deserve the systematic 

 rank of subfamilies, to be classed under the head of the one or the other of 

 the 2 above-mentioned families. In the sequel a short characteristic of these 

 subfamilies will be given in addition to the diagnoses of the chief families. 



Fam. 1. Cypridae. 



Characters of the family. Shell in most cases thin, corneous, only seldom 

 of a more solid consistency, surface smooth, never roughly sculptured, hing 

 simple, without any closing teeth. Ocellus, when present, generally simple, 

 not divided. Anterior antennae scarcely at all geniculate, basal part more or 

 less dilated and divided into 2 or 3 segments, terminal part attenuated, 4- or 

 5-articulate, and clothed with numerous more or less slender setae forming 

 together a dense apical brush. Posterior antennae originating by a short and 

 somewhat imperfectly defined root-joint followed by a much larger joint, 

 which constitutes the main part of the basal portion, the latter provided at- 

 the end outside with a small scale-like appendage carrying a slender anteriorly 

 curved seta accompanied by one or two very small bristles; terminal part 

 abruptly curved downwards and composed of 3 or 4 somewhat unequal joints, 

 the 1st of which is generally the largest and provided behind with a more or 

 less developed sensory appendage, at the end inside with 4 or 5 densely 



