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lines along the edges of the branch. Papillz are shaped similar 
to those of Sz/phium (Fig. 7). : 
Iva (Fig. 8-10). 
Jf. xanthitfolia, Nutt. The style of sterile hermaphrodite 
flowers is undivided, narrow at the base, and gradually enlarging 
to the tip. The brush hairs are in a truncate tuft at the tip of 
the style (Fig. 9). Brush hairs obtuse and not as long as in Sz/- 
phium (Fig. 10). The branches of the pistillate style are short, 
acute, with the stigmatic papilla in two lines along the edges. 
The papillz (Fig. 8) are more acuminate than in Si/phium. 
Xanthium (Fig. 11-13). 
A. echinatum, L. The style of the sterile hermaphrodite 
flower is nearly cylindrical, undivided, with brush hairs covering 
the entire surface for about one-fifth of the length of the style 
(Fig. 12). Brush hairs broadly obtuse (Fig. 13). Stigmatic 
papillz are rather large and somewhat acute (Fig. 11). 
Division II. 
Flelianthus, (Plate CXIX, Fig. 27, 28). 
H. rigidus, Desf. The branches have a triangular shaped 
tip with the brush hairs covering the entire outer face and the 
tip of the inner face. The stigmatic papilla cover the entire 
inner face except the tip (Figs. 27, 28). The brush hairs are 
large and acuminate. In H. ¢uderosus the three cleft style was 
also found. In some of these three cleft styles it seemed as 
though the third branch was formed by the division of one of 
two original branches, but in most cases all three of the branches 
were of equal length and seemed to be wholly separate. 
Heliopsis (Fig. 14, 15). 
H. helianthoides (L.), B. S. P. The style is the same as in 
Helianthus. The brush hairs do not cover the entire outer sur- 
face, but only the outer tip. The papillz cover the entire inner 
face, or are in two very wide lines, appearing as one wide line 
occupying the whole inner surface. 
_ The stigmatic papilla (Fig. 15) are larger than those of S7/- 
phium, while the brush hairs (Fig. 14) are smaller. 
