COOKE : ON THE MACANDREW COLLECTION. 355 



but the present is much more ovate, ventricose, and not 

 nearly so abruptly and angularly truncated at the 

 posterior end. 

 Thracia pubescens Pult. Plymouth. 



Four fine specimens — the largest 3*25 inches broad 

 by 2.15 long. 

 T. convexa Wood. Cornwall, Bantry and Belfast. 



Three specimens from as many localities. The 

 smallest is singularly aberrant, having the beaks almost 

 central, and without the peculiar arch or curve, while 

 the ridge is almost obliterated. 

 T. convexa Wood. Hebrides. 



Five very young specimens. 

 T. distorta Mont. Isle of Man. 

 T. distorta Mont. var. truncata. Portland. 



Seven characteristic specimens. 

 Poromya granulata Nyst. Croulin Island. 

 Two specimens, one full grown. 

 Nesera abbreviata Forbes. Loch Fyne. 



Ten specimens. « 



N. COStellata Desh. Loch Fyne. 



Four specimens, one half an inch broad. 

 N. cuspidata Oliv. Loch Fyne. 

 Corbula nucleus L. Anglesea, &c. 

 C. nucleus L. var. rosea. Weymouth. 

 Mya arenaria L. Britain. 



Largest specimen 3*0 inches broad by 5*0 long. 

 M. arenaria L. Beaumaris and Zetland. 



Young specimens. 

 M. arenaria L. Bantry and Dublin. 



Young specimens. 

 M. truncata. Britain. 



