EXPERIMENT STATION REPORT. 27 i 



In the matter of color there were seven plants distinctly purple 

 in stem, leaf and pod, and 29 in which the color, sometimes 

 quite pale, was confined to the pods. In other words, there 

 were 36 with color to 64 of the plain green type. 



The pair of leaves per stem ranged as follows : 



Number of pairs 7 8 9 10 11 12 13 14 15 16 



Instances 2 6 12 21 15 20 13 8 2 1 



There is an unexpected small number for the 1 1 pairs which 

 should be 25 instead of 15 when the series is considered math- 

 ematically. 



The length of leaves is expressed in the following scheme : 



Centimetres 4.3-5 5-6 6-7 7-8 8-9 9-10 10-11 11 



Instances 6 17 33 28 10 4 11 



In a similar wa_y, the breadth of the same set of leaves is 

 given below : 



Centimetres 1-2 2-3 3-4 4-5 5-6 6 



Instances 10 31 40 15 3 1 



The leaf was quite distinctly flat in 61 instances and wavy 

 in 39; and the tips were blunt, occasionally retuse in jy leaves 

 and pointed in 23 cases. 



In length, the pods (follicle) varied greatly and in a general 

 way may be grouped under long, 20 ; medium, 37 ; and short, 

 43 ; while in number upon the stem, they were as follows : 



Number of pods 1 2 3 4 



Instances 41 39 16 4 



Plate XXIII shows 70 leaves of the Green Milkweed from as 

 many plants taken at random, not included in the above one- 

 hundred, and arranged somewhat in a series from the narrowest 

 to the broadest in four rows from left to right. 



Dr. Gray records two varieties for Acerates znridiflora, namely, 

 var. lanceolata Torr. {A. lanceolata Ives) and var. linearis, a 

 western form. Minnesota to New Mexico, which does not seem 

 to need attention here. Britton and Brown recognize A. viridi- 

 flora Ivesii as the variety of the eastern range with the lanceo- 

 late or oblong-lanceolate leaves. In the present study, it would 

 seem that through crossing, etc., the species and its recorded 

 variety are so intergraded as to make the latter of little botani- 

 cal value. 



