2: 



terest in tliis rather peculiar lamellibranch.. It is a pleasure 

 to ackno-wledge my indebtedness to liim, I wish publicly to ac- 

 knowledge my indebtedness to ray wife, wlio has materially aided 

 me in securiiig, tending and preserving specimens, 



ANATOIIT AND HABITS. 

 The distincti-re characters for the genus Yoldia as given 

 by Verrill and Bush ^^■'•) are : "shell nearly smooth, compressed, 

 lanceolate, gaping, more or less prolonged and tapering posterior- 

 ly, with a well- defined wide rostrum, generally withotit carina- 

 tions. The external liganent is marginal, feebly developed, 

 continuous under the beaks and not much differentiated from the gen- 

 eral epidermis. The Chondrophore is large, concave, and pro- 

 jects within the margin. The pallial sinus is large and deep. 

 The siphon-tubes and posterior pallial tantacle are long. The 

 palpal tentacle^ are long and tapered ; in life they may extend 

 nearly to the end of the expanded siphon.' 



SHELL. 

 Figures 1 and 2. 

 To the above characters of the shell will be added a few 

 others, part of which, no doubt, are comriion to all the species 

 of the genus, while others are specific. 



