PERCENTILE PROPORTIONS OF LAKE AND ATLANTIC SALMONS. 133 



Both male and female lake salmon have higher proportions of the mandible than do 

 the Atlantic salmon. The proportion of the mandible of the 12.8-inch male Presumpscot 

 salmon is seven per cent higher than that of the 13.9-inch Atlantic male and that of the 

 16.5-inch Sebago female is five per cent higher than that of the 16.3-inch Atlantic female. 



Base D. — In the proportions for base of dorsal there is very little range in either the 

 lake or Atlantic salmon, but that of the latter is a httle greater. While this dimension 

 is not strictly in the categories under discussion since there is only one length class of 

 Atlantic salmon which would exclude a number of length classes of lake salmon from 

 equalUng parr only, it is here included. 



The single-length class of Atlantic salmon which, in this proportion equals the parr 

 is the 13.9-inch male, which is the highest of the Atlantic salmon excepting the parrs. 

 In the lake salmon there are five length-classes which equal the 6.5-inch male and female 

 parrs. These are the 12.8-inch Presumpscot male, the 17.6-inch Grand Lake male, the 

 16.5-inch and 18.9-inch Sebago females and the 19.3-inch Grand Lake female. The lake 

 salmon thus averages sUghtly higher than the Atlantic salmon in this proportion. 



Base A. — The ranges of proportions for this dimension are very restricted but that 

 of the lake salmon is a Uttle greater than that of the Atlantic salmon. However, there is a 

 difference shown in that seven of the eight length-classes of Atlantic salmon have the 

 proportions of the base of anal equal to that of the 6.5-inch female parr, while four of 

 ten length-classes have the same proportion and four others are equal to the 6.5-inch 

 and 8.4-inch male parrs only. Yet these proportions seem to have no connection with 

 size, sex or breeding condition of the fish. 



Height D. — The proportions for height of dorsal, except for one length-class of lake 

 salmon, are like those of the Atlantic salmon. By them there is nothing shown to dis- 

 tinguish the lake salmon as a whole from the Atlantic salmon. The smgle exception is 

 that of the Grand Lake breeding male, the proportion of which equals the 8.4-inch male 

 parr only. 



Height A. — The ranges of proportions of height of anal are essentially the same in 

 both lake and Atlantic salmon. But the same proportions are somewhat differently 

 distributed in the lake salmon than in the Atlantic length classes. The 12.8-inch non- 

 breeding Presumpscot male, the 14.7-inch Presumpscot breeding male, the 17.6-inch 

 Grand Lake breeding male, and the 25.5-inch breeding Sebago male have the same 

 proportion as the 28.3-inch breeding Atlantic male and the 6.5-inch male parr. Inasmuch 

 as the proportion for the breeding Atlantic male appears to have been increased over 

 immediately lower length-classes incidentally to development of breeding condition, 

 it would seem that the relationship of the above listed lake sahnon is properly with the 

 parr of the Atlantic salmon. 



Length P. — The 12.8-inch non-breeding male and the 13.2-inch non-breeding female 

 of the Presumpscot have the highest proportion of the lake salmon and higher than any 

 of the Atlantic salmon. The 14.8-inch breeding Presumpscot female and the 18.9-inch 

 breeding Sebago female have the lowest proportion of the lake salmon and lower than 

 any of the Atlantic salmon. 



