CYTHERIDEA. 181 



We have seen only one perfect specimen of this species, which was found by Mr. 

 Hobertson amongst some clay from Norway. Detached valves, however, are not uncom- 

 mon in some of our British clay beds, and a few examples, also separated valves, have been 

 dredged in Shetland, and off the north-western shores of Scotland, in considerable depths 

 (60 fathoms and upwards) of water. 



Distribution. Becent. — Norway, Scotland, Gulf of St. Lawrence, Spitzbergen. 



Fossil. — England : Bridlington. Scotland : Elie, Dryleys, Errol, King Edward's, 

 Tangyburn. Norway and Canada: Post-tertiary beds. 



6. Cytheridea (?) iNORNATA, 71. sjj. Plate VII, figs. 3 — 6, 



Carapace, as seen from the side, oblong, subreniform, highest behind the middle, 

 greatest height equal to more than half the length. Anterior extremity obtusely, pos- 

 terior boldly and obliquely rounded ; superior margin forming a flattened curve, highest 

 at the posterior third, inferior rather deeply sinuated in the middle. Outline as seen 

 from above compressed, ovate, width considerably less than half the length. Surface per- 

 fectly smooth. 



Length, g^rd of an inch. 

 Except for its occurrence in company with distinctly marine species, we should 

 almost have placed this in the genus Candona, to which it bears a very strong resem- 

 blance. Some undoubtedly marine forms have, however, been described {Cytheridea 

 Zetlandica, Brady, and C. nobilis, Brady), which present very similar characters ; but in none 

 of these cases have the recent animals been procured in a state fit for anatomical exami- 

 nation. Their present generic position must consequently be looked upon as merely 

 provisional. 



Distribution, /os5z7. — Scotland : Annochie. 



7. Cytheridea elongata, Brady. Plate IX, figs. 10 — 13, 



1850. Cythere ANGUSTATA, J5aiVJ (not of Miinster). Brit. Entom., p. 172, pi. xxi, 



fig. 6. 

 1868. Cythekidea elongata, Bradi/. Monog. Rec. Brit. Ostrac, p. 421, pi. xxviii, 



figs. 13—16 ; pi. xl, fig. 6. 



Carapace, as seen from the side, elongated, subreniform, higher behind than in front, 

 greatest height situated near the middle and equal to considerably less than half the length ; 

 anterior extremity evenly, posterior obHquely rounded ; superior margin forming a some- 



