52 



LAND AXD FRESri-WATER SHELLS OF N. A. [PART IL 

 KiisTER in Ch. ed. 2, 44, pi. viii, f. 



Fig. 76. 



Moll. 73, pi. iv, f. 77 (1843) 



8—10 (^Limnxus). 

 Limneus ontariensis, Muhlfeldt in KiisTEK. 

 Limnsea serrata, Haldeman, /. c. 



It is said to have been found from New England to Washing- 

 ton Territory. 



Considerable doubt exists regarding this variable shell, and its 

 identity with L. catascopium. It is referred to that species by 

 Stimpson (Shells of N. E. 32) and Gould (Lake 

 Superior). Subsequently it has been referred to 

 L. elodes, by Lewis (Boston Proe. Y, 122). I 

 have, therefore, given several figures of it in addi- 

 tion to the description of Mr. Say, leaving the 

 question of its specific weight to be decided when 

 more material has been collected. Fig. 75 is a 

 copy of Mr. Say's original figure in the American 

 Conchology. Fig. 77 is copied from one of Halde- 

 man's, drawn from an authentic specimen of Mr. 

 Say. A larger, better developed form, presented 

 to the Smithsonian (No. 9144), by Prof Haldeman, is drawn m 

 Fig. 78 ; while a somewhat peculiar 

 form is copied from Haldeman in Fig. 

 78. He suggests for it the name L. 

 serrata, should it prove distinct, and 

 describes it as characterized by ele- 

 vated lines and undulating peritrerae. 

 Kiister, I. c, places in the synonymy 

 of emarginata a var. A, L. ontariensis, 

 Muhlf. in litt., with an ovate-conic 

 shell, acuminate, whirls convex, the 

 last ovate, aperture semioval. 

 Fig. 79 gives, at one view, the various -forms of L. emarginata. 



Fig. 79. 



Fig. 77. 



Fig. 78. 



