RECENT BRITISH OSTRACODA. 



411 



20. Otthere villosa (Sars). (Plate XXIX. figs. 28-32). 

 Cythereis villosa, Sars^ loc. cit. p. 42. 



British type. Distribution : Recent — Great Britain and Ireland, Norway, Bay of Biscay. Fossil — 

 Glacial clays and raised beaches, Scotland, Ireland, Norway. 



Carapace of the female, as seen from the side, oblong quadrangular, nearly equal 

 in height throughout ; greatest height equal to more than half the length. The anterior 

 margin is obliquely rounded; the posterior truncate, angular, and somewhat waved. 

 The dorsal margin forms a flattened arch ; ventral margin straight or slightly sinuated, 

 swelling near the posterior, and sometimes also near the anterior extremity into an 

 angular protuberance. The outline, as seen from above, is compressed oblong, its sides 

 nearly parallel and tapering suddenly at each extremity, width equal to more than 

 one-third of the length; the contact-margins bordered by prominent ribs. End view 

 ovate, narrowed above. Hinge-joints as in C. alboniaculata. The surface of the shell 

 is marked with large and deep excavations, which tend to coalesce, and form, especially 

 towards the ventral and posterior borders, irregularly waved ribs and furrows. There is, 

 however, much variety in the amount and character of the sculpture, as well as in colour, 

 which ranges from white or yellow to a deep slaty blue. The form and proportions 

 of the carapace are also very variable, though the essential characters of the species 

 are mostly well preserved. The male is much elongated, about twice as long as high. 

 Animal almost exactly similar to that of C. angulata. The second antenna has an 

 armature of three setse similar to that of C. cowcexa. 



Length in. 



Hah. Littoral and in deep water. Shetland, Tobermory, Berwick, Isle of Skye, Plymouth, Exmouth, 

 Youghal, alive in tidal pools at Herm, Lamlash Bay, and Loch Carron ijiev, A. M. Norman) ; 

 Orkney {Mr. C. W. Peach) ; Aberdeenshire coast {Mr. Dawson) ; Cumbrae, Macduff, Peterhead, Ler- 

 wick, and Oban {Mr. D. Robertson) ; Cowes, Margate, Girdler sand and Donegal Bay {Mr. E. C. 

 Davison) ; the Minch and Channel Islands {Mr. Jeffreys) ; Devonshire coast {Mr. C. S. Bate) ; Norfolk 

 coast {Mr. D. 0. Drewett). In shell-sand from South Wales, Stranraer, Galway Bay, and Round- 

 stone ; dredged in Birterbuy Bay, 15 fathoms, and Northumberland coast, oflP Holy Island, 45 fathoms 

 {G. S. B.). 



This species, like C. convexa, is almost exclusively confined to the laminarian zone, 

 the instances of its occurrence in a living state between tide-marks being comparatively 

 rare. It appears to be a common species in our seas, except on the eastern coast, 

 where it is rare — in this respect, also, agreeing with C. convexa. It occurs plentifully 

 in the Glacial clays of Scotland and Norway. 



21. Cythere ? SEMiPUNCTATA, n. sp. (Plate XXIX. figs. 33-37.) 

 Distribution : Recent — Ireland, Bay of Biscay. 



Carapace of the male (?), as seen from the side, subelliptical, rather higher in front 

 than behind ; greatest height equal to more than half the length ; extremities rounded ; 

 superior margin nearly straight in front, gently curved behind ; inferior slightly sinuated ; 

 margins at their outermost edge thickened and elevated, but depressed inwardly, thus 

 forming a shallow excavated channel round the anterior and ventral portions of the 



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