78 Richard H. Boerker 
Black Hills 
Arizona and New Mexico 
Colorado and Wyoming 
Idaho and Montana 
Washington, Oregon, and California. 
It is a striking fact in the case of Pinus ponderosa that the 
size and weight of the seed and their manner of germination 
follow exactly this same order. The smallest seeds come from 
the Black Hills and New Mexico and the largest from California ; 
the total weight of 500 seeds is least in the case of the Black 
Hills variety and greatest in the California variety, hence the 
number of seeds per pound is greatest in the former and smallest 
in the latter variety. Furthermore, germination begins sooner, 
the germination period is shorter and the germination curve rises 
more rapidly in the case of the South Dakota and New Mexico 
variety than in the case of the Pacific coast variety. Some of 
these striking relations between seeds and site are also shown by 
Pseudotsuga taxifolia. This species shows all these relations 
except those of weight of seed and number of seeds per pound. 
There seems to be no definite relation in this respect. 
On page 79 the germination curves of the climatic varieties of 
Pinus ponderosa and Pseudotsuga taxifolia are given and they 
illustrate very forcibly what has been said above concerning the 
behavior of these curves. 
In order to determine the effect of the size of the seed upon 
the size of the seedling shortly after germination, the seedlings 
were dug up very carefully as they were counted and taken to the 
laboratory and measured. The total length of the hypocotyl and 
tap root was taken in each case, the seed being excluded from the 
measurement. These measurements were kept separate for the 
small and large seeds and the results are given below: 
Pinus ponderosa (Idaho)—Age, 2 Days 
200 seedlings from small seeds averaged ............... 3.07 cm. 
200 seedlings from large seeds averaged ............... 3.90 cm. 
These 400 seedlings were classified according to their total length 
as follows: 
