the Genus Streptopogon. 
12 1 
the marginal teeth are small and formed just as in the 
Madagascan plant (see Fig. 6). 
In ‘ S'. Parkeri, Mitt, mss/ the leaves have the cells of exactly 
the same size as in S. Rutenbergii , i. e. they are distinctly 
larger than in typical 5. erythrodontus ; the leaves, however, 
differ from those of the usual form of S. Rutenbergii in being 
narrower, and are erecto-patent and more or less crowded, not 
laxly arranged and patent or patulous. The limb of the leaf 
also is continued right up to the extreme apex. The in- 
florescence of ‘ S. Parkeri ’ is autoicous, the male flower, as in 
S'. erythrodontus , being borne on the stem, in the axil of a leaf, 
either immediately below the perichaetium, or a little way 
below it. In all characters, therefore, except in the laxer 
areolation, ‘ S'. Parkeri ' agrees with S'. erythrodontus. 
The characters shown by these two plants — 5. erythrodontus 
var. intermedins and S'. Rutenbergii — seem to me to afford 
evidence that the Madagascan plant is too closely allied to 
S. erythrodontus to be allowed specific rank. I have seen 
specimens of c S'. Hildebrandtii ’ in which a leaf here and there 
showed an areolation scarcely if at all laxer than that of 
vS. erythrodontus var. intermedins , and it is quite possible that 
further search in other districts of the Andes will bring to 
light South American forms of erythrodontus identical with 
the Madagascan plant. As a rule, however, the cells of the 
Madagascan plant are distinctly larger than those of the 
South American S. erythrodontus var. intermedins , and for 
this reason I have kept the two plants distinct. The cells 
of the Madagascan plant have the walls thicker than is usually 
the case in S'. erythrodontus type, so that the areolation is 
firmer. This character, however, is not absolutely distinctive. 
I have seen specimens of 5. Rutenbergii in which the leaf- 
cells have the thin delicate walls characteristic of S'. erythro- 
dontus type ; on the other hand I have found in several 
specimens of S', erythrodontus leaves, from the lower part 
of the stem, showing cells with the firmer and thicker walls 
of the Madagascan plant. This is the case, for instance, with 
the specimens collected by Weir, nr. 169, in Colombia (in the 
