MUKID^— AKVICOLIN^— ABVICOLA RIPAKIIJS. 



169 



exactly one and three-jijths inches ; and a foot of 0.78, or nearly four-fiflhs of 

 an inch. The innjority of the specimens run from 4.25 to 4.50 in Iciiglli; n 

 large proportion run between 4.00 and 5.00. Only eight specimens (al)out 7 

 jMjr cent, of the whole) exceed 5 00, and only twelve (about 10 per cent.) of 

 the adult ones fall below 4.00. The proportionally longest tail is as 0.41 to 

 1.00, or a trifle over two-fifths of the trunk; the shortest tail is as 0.27 to 1.00, 

 or a little over one-fourth of the trunk; the average tail is to the average trunk 

 as 0.37 to 1 .00, or about three-eighths. Only a single foot of the 1 14 (ixcccds 

 0.90, and only three touch this figure; not one fulls below 0.70. 



The limits of what may be called normal individual variability are easily 

 set from the foregoing figures, and the bounds of (Hissible variation as readily 

 |)erceived for both al)8olute size and relative proportion of parts. It must 

 be observed that we have not yet presumed to inquire whether more than 

 one species be represented in the series; but what we claim to have shown 

 is that no more than one species can be predicated upon these specimens 

 from size and relative proportion of parts, since the ab&olute dimensions gnidc 

 imperceptibly between the extremes, ond the relative measurements are 

 inextricably interlaced. 



As a supplement to the foregoing, we subjoin another table of more 

 detailed measurements of numerous alcoholic specimens, all from the Eastern 

 United States. This table extends and checks the above results to the last 

 details of structure, and requires no further comment. 



Tablr XLSII.— Jtfiramimimto effortji-fitt (and IM nf Many othtr) alBokoUe ipteimau q/ A. miparicb flrom 



Ikt Saltern U»UedSMt$. 



■y-:'U 



< i 



t 







