250 BOTANICAL GAZETTE. [ October, 
nest, the pollinia of the two Acerates kept their proper posi- 
ti ow, when such insects visit flowers of the species to 
which the pollinia belong, full fertilization may take place— 
cross-fertilization, too, since they have wandered so far from 
the original plants. 
e modifications of the floral structure of different 
species enable the plants to avoid competition for the/same 
insects, or for the same parts of the same insects. Thus, 
bumble-bees have pollinia of Asclepias Sullivantii on their 
claws, of A. verticillata on their tarsal hairs, and of Acerates 
longifolia on the hairs of the ventral surface. 
$ an interesting peculiarity of Asclepiads may be men- 
tioned, the occurrence of pollinia in positions in which the 
flowers are not specially adapted to place them. It has been 
observed that Asclepias sometimes fastens pollinia on the 
tongues of insects. Acerates longifolia accidentally catches 
the hairs of the face and tongue. In contrast with the 
Acerates, is Xysmalobium lingueforme, whose pollinia, ac 
cording to Mansel Weale,” are found regularly on the insect s 
head, but only accidentally on the hairs of the tarsi and ven- 
tral surface. 
BRIEFER ARTICLES. . 
: * Indicative” Eriogonums.—The mountains of Montana are not very 
high, but they are numerous, 
nitory. Almost wherever prospected they yield precious metals, in some 
‘jad’ some knowing old prospector hunting “signs” as well as 8° 
a. 
