234 BOTANICAL GAZETTE [march 



protuberences i mm. or so in length. Very little elongation had 

 occurred, but clear evidences of its inception were to be seen. 

 Growth in length had already begun. 



This early study, as well as the subsequent ones, also brought 

 out another interesting point in regard to white pine roots, namely 

 that there are two kinds of roots underground, just as there are 

 two kinds of branches above. This is well brought out in fig. ii, 

 where long roots and short roots are plainly visible. The short 

 roots occur irregularly on the sides of the long roots, either singly 

 or in tufts of varying size. Where the latter occur, they arise 

 through the forking of a normal short root; this is repeated a 

 number of times and each branch remains short and acquires a 

 growing point of its own. Occasionally one of the apices in the tuft 

 grows out into a long root, but the majority of them remain short, 

 function for a time, but eventually die and disappear as the diameter 

 of the long root increases. Other workers have already noted 

 the same condition in white pine roots. Busgen (4) has described 

 it in some detail, and adds further that mycorhiza are found in the 

 long roots, while they are entirely lacking in the short roots. 



Data bearing on root growth were next obtained on May 10. 

 Roots were taken from a thrifty young pine about 12 years old, 

 which from its position on the north bank of Fall Creek near Varna, 

 N.Y., was admirably fitted for the purpose in hand. The creek had 

 partially imdermined the sandy bank, and root apices were readily 

 obtained by digging back into the bank. Some of these are repre- 

 sented in fig. 12. The new growth had already attained a length 

 of two inches in many cases, and, as seen in the figure, was sharply 

 marked off from that of the preceding year. This is due to the 

 fact that in the last cork formation (as well as secondary thicken- 

 ing) had occurred, and the thick primary cortex which forms the 

 bulk of the thickness in the new growth was entirely lacking. 

 Browning of the tissues, a peculiarity already described, had also 

 started in the new growth, as the root tip at the extreme right 

 bears evidence. Lateral roots in the form of translucent dots 

 were just appearing on the sides of the growth of the preceding 

 season. It was quite impossible on May 10 to make comparative 

 notes of root growth in 1912 and 1913, inasmuch as the point of 

 origin of growth in the spring of 191 2 was not evident. All trace 



