Occasional Papers of tJic Museum of Zoology 5 



Variation in the Xuntbcr of Anal Rays in Cottiis )ncridionalis 



Locality Anal rays 



10 II 12 13 14 15 



Illinois: Lockport and Joliet — — i 65 I 



Indiana : Ft. Wayne — i 2 5 2 — 



Indiana: Cherry Creek — 8 18 i — — 



Missouri : Several localities i 2 7 8 — — 



Arkansas : Batesville — — ■ — 7 — 



Alabama: Florence — 2 7 6 — — 



Cottus bairdii Girard 



Cottus richardsonii Agassiz, Lake Superior, 1850, p. 300; Girard, 

 Smiths Contr. Knowl., 3, 1851, p. 39, pi. i, figs, i, 2. (Not Trachidermis 

 richardsonii Heckel, 1840, also a species of Cottus, synonomous with 

 Cottus aspcr Richardson, 1836.) 



Cottus bairdii Girard, Proc. Am. Ass. Adv. Sci., 2, 1850, p. 410; 

 Proc. Boston Soc. Nat. Hist., 3, 1850, p. 189; Smiths. Contr. Knowl., 

 3, 1851, p. 44, pi. I, figs. 5, 6. 



Cottus- zcilsonii Girard, Smiths. Contr. Knowl., 3, 1851, p. 42, pi. i, 

 figs. 3, 4- 



Cottus ictatops Jordan and Evermann, Bull. U. S. Nat. Mus., 47, pt. 

 2, 1898, p. 1951 (in part; apparently not Pegedictis ictalops Rafinesque). 



This species or subspecies seems to be a northern form of 

 Cottus meridionalis. It occurs with (or near) Cottus gracilis 

 or its representative, C. fra)iklinii, in the upper Ohio basin; in 

 Cayuga Lake, New York; in Lake Superior; and probably in 

 intervening locaHties. Specimens in the Field Museum of 

 Natural History, referable to Cottus bairdii, were taken in 

 Cayuga Lake, New York, and at Sault Ste. Marie and Lizard 

 Islands, Lake Superior. Like Girard's specimens, which he 

 referred to richardsonii, bairdii and Zi.'ilsonii, those at hand have 

 the anus mor'e posterior than in Cottus meridionalis. 



One of the diagnostic features of C. zcilsonii as defined by 

 Girard, is the branching of the pectoral rays. In the series 

 from Cayuga Lake, agreeing in most details with Girard's 

 description and figure of zvilsoiiii, one specimen has two 



