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. jjerallum, 1. c); creek below 

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

 1904); Flat Cieek, Pettis Co., Mo., bj Mr. F. A. Sampson, and 

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

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



This differs from P. perakum 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 peraUum is pale 

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

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

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

 far as known ; P. fraiidulentum 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 he Conihmed.') 



NOTES. 

 CiNCIXNATIA 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 Cincimiatia cinchmatiensis Anth. and 

 the following other species of shells : Planorhis antrosus Conr. 

 parvus Say; dilataius Gld.; Lymnaea columella Say; Pbysa hetero- 

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

 Amnicola limosa Say ; Lyogyrtis granum Say ; MuscuUum trans- 

 versum Say ; Pisidium norehoracense Pr.; variahile Pr.; compressum 

 Prime. So far as I know, this is the only record of C. cincmnaU'ensis 

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

 the Potomac River E. G. Vanatta. 



