Kendall — Notes on Percopsis guttatus and Salmo omiscomaycus. M> 



Notes applying to the above comparison. 



1. Jordan and Evermann give the maximum length of Per- 

 copsis [villain* as ('» inches. The species will not average over 4 

 or 4^ inches in specimens at hand. 



2. The branchiostegals are not uniformly 6. In several 

 specimens examined by the writer there are only 5 on a side. 



3. There are only eleven developed dorsal rays, the spines 

 being small, inconspicuous and adherent to the first ray. 



4. Anal uniformly with 7 developed rays with inconspicuous 

 rudimentary spine adherent to the first ray. 



5. Ventral rays are uniformly 8. 



6. Caudal fin always strongly forked. 



7. Pectoral varies in number of rays. 



8. The teeth of even a 4i inch trout or salmon would hardly 

 be called " minute." 



9. Seldom more than two rows of spots on the side of the 

 back and one row along the dorsal median line. 



The characters conspicuously distinguishing the Omisco May- 

 cus from any Salmonoid are: 



No Salmonoid has so few branchiostegal rays. Coregonus 

 quadrilateralis according to Richardson, sometimes with 8 rays, 

 comes nearest to it, but the number of anal rays in the white- 

 fish far exceed the number in Percopsis. 



No Salmonoid other than some white fish has so few ventral 

 rays, and as previously mentioned the anal of the whitefish 

 exceeds the Percopsis in number of rays. Besides no whitefish 



* 



has teeth on its jaws. 



The teeth of the salmon or trout are comparatively large. 



Salmo salar is not recorded from Hudson Bay. Lowe men- 

 tions it as occurring in Ungava Bay, the most westward point of 

 its range. 



Cridivomer namaycush and perhaps one or more species of 

 Salvelinus occur in the region but the characters above mentioned 

 preclude these forms. 



In his Families of Fishes, 1872 (Smithsonian Miscl. Collec- 

 tions), Gill included the Family Percopsidae in the order Isos- 

 pondyli, to which, from the structure of the species, it would 

 seem that it was more closely related than to the Acanthopteri, 

 owing to the fact that the so called spines are very weak and 

 similar to the usual simple or rudimentary rays of the Cyprin- 



