LIFE HISTORY OF DESMOGXATHUS FUSCA. 



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GRAPH IV., showing a comparison of the proportionate lengths of body regions 

 during the aquatic larval period (lines a-/), metamorphosis (line/), and the first 

 two years of adult life (lines /-z) ; also the proportionate lengths of body regions 

 of the average of 10 miscellaneous adults (line j). Based upon the statistics given 

 in the second cclumn of Table II. 



The time ratios shown by the horizontal measurements and the dates expressed 

 by the location of the vertical lines are as in Graph III. Note that by the end of 

 the second year cf adult life (line /) the body proportions are those of the average 

 adult (line j). 



entirely freeze over. Thus I have always found, even in mid- 

 winter, a little open space, sometimes only a few inches in width, 

 and by breaking away the ice bordering the edges of this, have 

 been able to reach the quiet pools under the ice, in which larvae 

 are found. Specimens have in this way been collected in Jan- 

 uary when the temperature was at o F. and had been at that 

 point or lower for three or four days. 



