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zi 
Se tel emg a ee en ge ee eT ee Os ee ae RT Ng ee Ne ne ee ee cee Rae ee ee ee ee er 
1897] THE LIFE HISTORY OF SALIX 179 
Fig. 74. S. tristis. Embryo almost in cotyledon stage; dermatogen of 
root tip differentiated but still no separation into periblem and plerome. 
Fie. 75. S. glaucophylla. Shows dermatogen of root tip and the root 
cap; no differentiation into periblem and plerome. 
Fig. 76. S. ¢vistis. Dermatogen of root tip and several layers of the 
root cap ; periblem and plerome are probably independent. 
Fic. 77. S. glaucophylla, The lower karyokinetic figure marks the 
division by which the suspensor contributes the dermatogen of the root tip* 
and first layer of the root cap. 
Fig. 77a. S. glaucophylla, A somewhat later stage than fig. 77. . 
' 
PLATE XVIII, 
Fig. 78. S. fetiolaris. A normal pistil drawn for comparison. 
Figs. 79-88. S. fetiolaris. All drawn from material taken from a single 
monstrous plant. A short description of each figure is given in the text. 
