STATE GEOLOGIST. 113 



than in front. The lower edge of the shell is rather straight, while the upper 

 narrows behind, to form the more acute apex. The color is dull white, without 

 markings of any kind. 'Xhe shell is more gibbous than any of the other speeies 

 seen, and is quite glabrous. 



The antennae and feet are not protruded as far as in vidua. This species is 

 also abundant. 



Plate No. XVII. fig. 2. 



GENUS Candona, Baird. 



Baird's Brit. Entomost., p. 151. 



.Characters. — Distinguished from Cypris by the absence of the tuft of long hairs 

 on the secondary antennae, and the consequent creeping method 

 of locomotion, and, perhaps, by a difference in the form of the 

 maxillipeds. 



Candona ornata. Herrick. 



Kesembles in size C. lucens of Baird, and is of somewhat the same shape. 

 The lower posterior margin is acute, the lower margm is sinnated and the whole 

 margin is beset with hairs. The edge of the shell is also bordered by a series of 

 of markings; the antennse of the second pair are totally without setse as far as 

 observed; the shell is white and opaque with pearly lustre. This species is not 

 very gibbous. (See Plate No. XX., Fig. 1.) 



Candona (?) elongata. Herrick. 



Shell renifbrm, very elongate, white, glabrous; the umbones.of the valves are 

 about two-thirds the distance from the anterior to the posterior dorsal mai-gin; 

 the portion of the shell anterior to the prominence thus formed is narrower than 

 the posterior. It is questionable whether this be a member of the genus 

 Candona or in reality a Cypris. The animal is quite large and the structure was 

 more clearly made out than in the above. The same pair of bodies seen in the 

 male Cypris vidua was found in this animal, the form of the maxillipeds, more- 

 over, was found to differ from that given under the germs Cypris by Dana. It 

 is to be hoped that some one may be able to devote a little patient study to this 

 group and clear up the habits and structure as well as the history. 



SUB-FAMILY II. CYTHERIN^. 



Cytheridse, Baird, Brit. Entomostraca, 162. 

 Characters. — Feet six, all slender, alike and pediform. 

 Genus 1. Cj'there, Midler. 

 Shell thin and light, tail short. 

 Genus 2. Cythercis, T. R. Jones. 

 Shell corrugulate or tuburculate, animal unknown. 



FAMILY II. HALOCYPRID^. 



This family includs two sub-families and three genera of oceanic species differ- 

 ing in almost all the organs from the above. 

 8 



