PAPERS ON ZOOLOGY 149 
3. The Number of Rays in the Anal Fin 
The longer anal fin of boscii, containing more rays than that 
of crysoleucas proper, is the most important of the characters 
which distinguish the two forms. Within the species, includ- 
ing the two subspecies, the variation in the number of branched 
rays in the anal fin is from 8 to 17, more than one hundred per 
cent. A variation of five rays, which is unusually wide when 
the number is so low, occurs normally in a single lot from a 
single locality. Thus, in a series from Saginaw Bay, Michigan, 
the rays vary from 8 to 12; from Dewey Lake, Michigan, 10 to 
14; from the Huron River basin, Michigan; from Pikeville, 
Indiana, 9 to 13; from Lake Monroe, Florida, 13 to 17. 
The most intersting aspect of this variation in the number 
of branched rays of the anal fin is not its wide extent, but 
rather the geographical distribution of its variants. This is 
indicated in the two following tables. 
Tables showing the geographical variation in the number of 
branched rays of 465 specimens of Notemigonus crysoleucas. 
branched rays of 487 specimens of Notemigonus crysoleucas. 
Branched annal rays Localities (states) 
North Dakota, Wisconsin, 
Michigan, Ontario, Nova 
Scotia, Iowa, Northern Mis- 
souri, Illinois, Indiana, Ohio. 
s 9) 10 11 32 95.14 15,16 17 
1S Tie: Pip a We Sop i ce 
| 
Texas, Louisiana, Arkansas, 
, Oklahoma, Southern Mis- 
| Souri, Virginia, Maryland, 
[ Delaware, Pennsylvania. 
South Carolina, Georgia, 
eeiein® gate so ce ti. 412 238 141 
Alabama, Florida. 
