THE OTTAWA NATURALIST 



VOL. XXII. OTTAWA, AUGUST, 1908 No 5. 



LYMN.^A UMBILICATA C. B. ADAMS IN CAxNADA. 

 By Bryant Walker. 



The history of this species has been an unfortunate one. 

 It was originally described in 1840 from specimens collected at 

 New Bedford, Mass. Gould in 1841 (Invert. Mass. p. 218) 

 recognized it as a vaHd species. But Haldeman in 1842 (Mono- 

 graph, p. 34) referred it to L. caperaia Say. In this he was 

 followed by W. G. Binney (L. & F. W\ Shelis'Pt. II, p. 56, 1865) 

 and all subsequent writers with one exception. Dr Pilsbrv 

 in 1891 (Proc. A.N.S.P. 1891, p. 320) stated that umbilicata 

 was synonymous with L. cubensis Pfr., and "perfectly dis- 

 tinct" from both L. caperaia Say and L. humilis Say. " That 

 this opinion is correct, I have recently had the opportunity 

 of verifying from an inspection of one of Adams' original speci- 

 niens now in the Museum of Middlebury College, Vt. (Naut. 

 XXII, p. 7, 1908). The only Canadian citation for this species 

 that I know of, and for this I am indebted to Dr. J. F. White- 

 aves, is by D'Urban in 1860 (Can. Nat. VI. p. 97), who quotes 

 it from near the village of Grenville in the County of Ottawa. 

 "D'Urban was more of an entomologist than a'conchologist 

 and he expressly states that Dr. Isaac Lea named most of his 

 fresh water gastropods" (Whiteaves). As he does not cite 

 L. caperaia in his list, in the absence of his actual specimens 

 it is impossible to say whether the identification was correct 

 or not. Dr. Dall in his recent report on Alaskan Mollusks 

 (Harr. Exp. XIII p. 79) includes umbilicaia in the synonymy 

 oi caperaia but expresses "strong doubts as to the validity of 

 this species (caperaia) which may prove entirely heterogeneous." 

 But he does not attempt to differentiate the 'two forms. Nor 

 does he state whether the local references cited from the litera- 

 ture refer wholly to caperaia or not. Apparently no Canadian 

 specimens of either form had been examined by him. In 1880 

 Mr. G. C. Heron (Trans. Ott. Field-Nat. Club No. 1, p 39) 



