NO. 180I MILLKRS-THUMB AND ITS HABITS — GILL II5 



COTTUS RICHARDSONII' 



Number of specimens, 50.- 



Number of males, 32. 



Number of females, i8. 



Number with ventral rays same on both sides, 45. 



Number with ventral rays 3 right and 3 left, 38. 



Number with ventral rays 4 right and 4 left, 7. 



Number with 3 ventral rays on right side, 42. 



Number with 3 ventral rays on left side, 39. 



Number with 4 ventral rays on right side, 8. 



Number with 4 ventral rays on left side, 11. 



Number with more ventral rays on right side than on left, i. 



Number with more ventral rays on left side than on right, 4. 



The only asperities found were a small patch of prickles in the 

 axilla of the pectorals, extending caudad as far as the end of the 

 pectoral. In 5 specimens (4 males and i female) these were ap- 

 parently absent. 



The sexes showed no noticeable differences in regard to the pec- 

 toral and ventral fins. 



In the specimens from Labrador the longest dorsal spine was 

 about 1/4 inch in males and about 3/16 inch in females, without re- 

 gard to the length of the fish. 



Males from Labrador were 21/8 inches to 3 9/16 inches long. 



Females from Labrador were 2 1/4 inches to 3 1/8 inches long. 



Males from other localities were 2 11/16 inches to 5 1/2 inches 

 long. 



' Tlic Coitus ricJiardsonii has l)ccn called Coftus iclalops in recent iclithyo- 

 logical works by reason of the assumption that it was tlie species intended by 

 Rafinesqne under the name Pcgedictis ictalops. Rafmesque's fish with "small 

 scales," "thoracic fins with five rays," and "second [dorsal] with twelve" rays 

 was, however, apparently the same as his Ethcostoma Hahcllare and B. fon- 

 tinalis. 

 ° Number of specimens from Labrador, 42. 



" Wytheville, Va., i. 

 " White R., Ind., i. 

 " Vermont, i. 

 " Evanston, 111., i. 

 " Alabama, 2. 

 ♦' " " " Marshfield, Mo, 2. 



