186 CHELONE GLABRA,—TURTLE-HEAD, 
stamen is produced to the length and of the strength of the four 
perfect stamens, though we can see it has still imperfect anthers ; 
but the fifth in this family being so conspicuously prominent, 
even to this extent, earned for the genus its botanical name 
Pent- (or fifth) stemon. Now, our present subject, Chelone (pro- 
nounced in three syllables), is much like Peméstemon in this 
respect, though, while the fifth or imperfect stamen is developed 
to the full length in Fzés¢emon, it is much shorter than the other 
four in our present subject, and botanists dwell much on this in 
noting the differences between the two. There are also some 
little differences in the peculiar compression of the corolla in 
Chelone, and in the general appearance; and, after all, it is a 
question whether it is not rather because of the general appear- 
ance of the plant and flower that it is kept separate from Pemt- 
stemon, for very few persons, unacquainted with the niceties of 
botanical classification, would at first take it for a Pemdstenzon. 
There is, however, one little point which seems characteristic and 
sufficient to decide them, and that is in the seed, which has always 
around it a broad membraneous wing, never to be found in Pezd- 
stemon, so that this, with the general distinct appearance, might 
be relied on to distinguish. But even the general appearance is 
not always to be relied on, for the “Botany of the Californian 
Geological Survey” tells us that there is a plant in Oregon so 
exactly like a Fenéstenon, that one has to note the membraneous 
border to the seeds before knowing that it is a Chelone. On the 
other hand, there are some /ezéstemons that have been thought to 
be Chelones, and the whole teaches us on how slender founda- 
tions often stand what we think are very distinct genera. 
As to how one form may grow out of another, a hint may be 
gathered from a communication by Mr. Henry F. Young to the 
Bulletin of the Torrey Botanical Club for 1872. As already 
noted in Che/one, the fifth or false stamen is much shorter than 
the others, but Mr. Young found a flower in which were five per- 
fect stamens, This isa very important fact as showing the line 
of descent. In this genus and most of its allies the calyx is five- 
