DIPLOPAPPUS LINARITFOLIUS.—SANDPAPER STAR: WORT, 15 
having perhaps been made acquainted with it by his correspondent, 
the Rev. John Bannister. Linnzus knew it as Aster Minaritfoltus, 
Michaux as Aster rigzdus, and Nuttall included it in his genus 
Chrysopsis as C. tinarifolia. The genus Diplopappus was founded 
by Cassini in a paper published in a Paris magazine in the early 
part of the present century. The genus Aséer is so very large 
that though the distinction between it and Diplopappus is small, 
the division, if at all well founded, must be acceptable to students. 
It will be noted by those fond of accuracy that the common con- 
struction of the specific name, linariifolius—that is, “leaves like 
or belonging to the linaria’”—is not according to Latin rules. 
Linaria should form its genitive linariz=linarizfolius, and we 
have to acknowledge our ignorance of any valid reason for the 
orthography in general use. 
The snecies affords a very pretty botanical lesson in the devel- 
opment of its axial buds to branches, and these again to flowers. 
As we see in our plate, no buds grow from the axils of the lower 
leaves, but gradually a few axillary leaves appear as the stem 
elongates, until the latter is suddenly suppressed, when the axial 
growths become stronger, and while some of them never become 
more than little branches, others go on to complete flowers. The 
sudden arrest of growth iu the main stem accelerates that of the 
branchlets, and we can see that it was this sudden stoppage of 
growth at the apex which gave the graded impulse downwards, 
and which resulted in the growth of the axial buds. Precisely 
the same effect is produced in any growing shoot by artificially 
arresting its growth—that is, by pinching out its terminal bud. 
We know that these sudden arrests or sudden accelerations of 
growth are the foundation of many wonderful changes in the 
forms of flowers and the general characters of plants; but atten- 
tion having but recently been drawn to these simple facts, the 
laws which induce these rythmic growths are not yet understood. 
Besides furnishing a valuable lesson in Lotany, it is a beautiful 
plant; and those who grow it in gardens generally esteem it 
highly on this account. It is one of the last of floral charms to 
