MEASUREMENT OF ORGANISMS. 



U 



Sinuate, still stroDger waves, height equals or exceeds 

 breadth (Fig. 19). 



Incised, with sharp, deep incisions (Fig. 20). 



15 



17 18 19 



FIGS. 15-20. 



The quantitative expression of variation in these forms can 

 usually be easily obtained by using an index, or ratio of two 

 dimensions. 



greatest length 

 Index of Lmearness, --^--^-^^. 



greatest length . 

 " " Lanceolateness, j - T^J^T,' also angle afo. 



greatest length area 



" Oblongness, greatest breadtu . ^ b^dth' 



(greatest Igth.) (greatest brdth.) 

 ^' (greatest 



for values from 1 to .50, 



