96 THE NAUTILUS. 



opposite "Washington, D. C. (No. 628), both in tide water, collected 

 by myself, Oct. and Nov., 1896; Bowling Green, Ky., Habana, 111.. 

 Iowa City, la.; as mentioned (under P. perallum, 1. c.); creek below 

 Elizabethtown, 111., collected by Mr. A. A. Hinkley, 1894 (received 

 1904); Flat Creek, Pettis Co., Mo., by Mr. F. A. Sampson, and 

 from the same place in Mr. Bryant Walker's collection ; north- 

 eastern Mississippi, collected by Mr. A. A. Hinkley. 



This differs from P. perdltum as follows : the superior margin is 

 somewhat less curved, the angle formed by it and the supero-anterior 

 slope is more projecting ; the mussel is larger but somewhat less in- 

 flated ; the color is corneous to yellowish, that of perahum is pale 

 corneous to nearly colorless or grayish, and the shell is more trans- 

 lucent; the surface of P. fraudulent urn is more dull. As written, 

 these differences may not appear striking, but they are constant so 

 far as known ; P. fraudulentum is remarkably uniform. 



It appears also that our species ranges near some forms of P. 

 compressum, and is of the same group ; but the mussel is not so 

 oblique, the beaks are broader and without ridges ; moreover, the 

 two were found associated at several places, and distinct. 



( To be Continued.^ 



NOTES. 



ClNCTNNATIA IN THE DELAWARE DRAINAGE. On October 1, 



1912 Mr. Delos E. Culver collected some pond-weeds at the settling 

 pond on Darby Creek near Addingham, Delaware Co., Pa., which 

 contained living specimens of Cincinnatia cincinnatiensis Anth. and 

 the following other species of shells : Planorbis antrosus Conr. 

 parvus Say; dilatatus Gld.; Lymnaea cohimella Say; Physa hetero- 

 stropha Say ; Campcloma decisum Say (one specimen is sinistral); 

 Ammcola limosa Say ; Lyogyrus granum Say ; Musculium trans- 

 versum Say ; Pisidmm noveboracense Pr.; variabile Pr.; compressum 

 Prime. So far as I know, this is the only record of C. cincinnatiensis 

 in the Delaware drainage, or anywhere between New York state and 

 the Potomac River. E. G. VANATTA. 



