150 ON SPECIES OF OSTRACODA, &e. 
Subfam. II. Cyturerinm, Dana. 
Genus Cytuere, Miiller. 
4, CyTHere conTorta,n. sp. (Pl. III. fig. 15.) 
Forma elongata, fabeeformis ; margines dorsalis, anticus 
et posticus arcuati; margo ventralis ante medium 
valde incurvatus, post medium subrectus; altitudo 
maxima pone medium sita. Forma desuper spec- 
tata compressa, in medio latissima, ad extremitates 
gradatim equaliter diminuens. Latitudo altitudine 
multo minor. Valvarum superficies levis, margarit- 
acea, polita, sparse et minute punctata, zona ciliorum 
prope marginem sita circumdata. Color albidus. 
Long. vix 4 une. 
Habitat mare ad Berwick in regione Northumbriensi. 
Elongated bean-shaped; dorsal, posterior, and anterior mar- 
gins rounded ; ventral margin deeply concave before the middle; 
the highest part of the valves is towards the posterior extremity. 
The form, as seen from above, is compressed, the breadth gra- 
dually and equally diminishing from the centre to the extremi- 
ties. The greatest diameter is greatly surpassed by the height. 
The surface of the valves is smooth, polished, and pearly, merely 
impressed with a few scattered punctures; encircling the valves 
at a short distance from their margin, runs a fringe of cilia 
ranged in single file, which forms a marked characteristic in the 
species. Colour white. Length not quite .% inch. 
Found among shell-sand at Berwick-on-Tweed, Sept. 1857. 
EXPLANATION OF PLATE IIL 
Fig. 1. Candona serrata (Norman), left valve, x 20. 
Fig. 2. The same seen from below, x 20. 
Fig. 3. The same seen from above, x 20. 
Fig. 4. The same; fragment of valves to show their structure and the 
; arrangement of the lucid spots, x 100. 
Fig. 5. Superior antenna of the same species, x 100. 
Fg. Inferior or pediform antenna of the same species, x 100. 
Fig. 7. Cypris aculeata (Liljeborg), right valve, x 40. 
D> ox 
