236 BOTANICAL GAZETTE. [ September, 
A study of Hydrangea as to the objects of cross-fertilization: 
by Tuos. MEEHAN. 
The author detailed a number of facts connected with the 
structure and development of allied species of Hydrangea, 
and argued that on no theory of evolution based on adapta- 
tion to insect visits could these changes occur. He con- 
tended that variety must exist in order to provide for order, 
and that variations, as we see in Hydrangea, can be of no 
ssn benefit to the plant, but exist for mere variety’s 
sake. 
A phase of evolution: by E. LEw1s STURTEVANT. 
Botanical varieties are the unit of evolutionary progress 
under vegetable culture, as evidenced by a study of cul- 
tivated and*wild dandelion. Colored drawings and her- 
arium specimens were exhibited demonstrating the sub- 
stantial identity of garden varieties with wild varieties, and, 
conversely, showing the types for new future varieties. 
[Discussed by Messrs. Campbell, Tracy, Riley, Lazenby 
and Meehan. | 
Votes on the inflorescence of Callitriche: by Jos. SCHRENK. 
_ The bracts of the inflorescence, which Caspary calls 
stipules and Schenk calls trichomes, the author finds to be 
bladders filled with air and with walls of a single layer of 
cells. The cavity of these organs is schizogenous and they 
are equivalent to phyllomes. Their purpose is to oN 
necessary buoyancy to the apex of the stem. A study 0 
the histology of the flower-cluster makes the author believe 
that the stamen and pistil constitute one flower, so that it 1s 
hot moncecious, as described, but perfect. 
[In the absence of the author, the paper was read by the 
Secretary. No discussion. | 
flygroscopic movements in the cone-scales of Absetinee: by 
be very efficient, first, in loosening the winged seeds ange 
scale which bears them, and second, in favoring the 
