1877 ] Botany. 177 
found to be perfectly erect and exserted 16” beyond the lobes of the peri- 
gone, or 7” beyond the stamens at their fullest development. The pap- 
ille have now extended laterally over the entire surface of the stigma, 
from which is freely secreted a clear, colorless, sticky liquid. 
The stigma is now perfectly developed, and ready to receive the pol- 
len grains ;* but it is more than forty-eight hours since the anthers dis- 
charged their pollen, and for the last twelve they have hung useless and 
effete, and-are already beginning to drop off. It is evident, then, that 
flowers of our Agave must depend for fertilization either on the very un- 
certain chance of some of the pollen discharged from the anthers of the 
upper flowers, dropping just at the right moment on the developed stig- 
mas of the lower and older ones, or on the visits of some nocturnal in- ~ 
sect, on the search for the abundant and attractive secretions contained 
in the tube of the perigone. Fertilization of the lower flowers is probably 
secured by both these agencies. Those placed higher up on the scape 
can only be made productive by pollen brought from other plants and 
placed on their stigmas at the moment of their maturity. — C. S. SAR- 
GENT. 
PayLLoTAaxıs or Cones.? — I wish here to supplement an article 
which appeared in the American Naturalist in August, 1873. Men- 
tion is there made of finding cones of several species in which the phyl- 
lotaxis of part of them consists in opposite leaves more or less spirally 
arranged, The fraction expressing the arrangement for scales on such 
Cones falls into the series 2, 2, is, ass #2, etc. One cone of a European 
larch was recorded having three, six, and nine spirals, and falling 
Pad the series 2, 3, 1, o%, 44, ete., or having the scales in whorls of 
three, 
This summer, on examining about three pecks of cones from one tree 
of the European larch, three more cones were found in which the arrange- 
ment of scales falls into the series beginning with decussate whorls of 
three. I have now found a single cone on which there are four spi 
Whorls in one direction, and four and eight in the opposite direction. 
The fraction expressing its phyllotaxis is y, and falls into the series 
beginning with decussating verticels of four, namely, $, yy) xy» 43, $$ 
rv Some of these cones were exhibited with the scales marked in 
in ‘ 
In reply to some questions of Professor Morse, as to whether all the 
Tonos had a phyllotaxis like the examples mentioned, Professor Beal 
remarked that the arrangement of most cones of the European larch was 
k at of alternate leaves, and was expressed by the fraction 3, falling 
into the series 4, b 2, x, etc. The fraction for a few cones with al- 
I have failed to detect in A. Yucceefolia any opening between the lobes of the 
ito) i t Appetit as noticed by Engelmann in A, Virginica, and by Jacobi (Ag. 
m t . 
; ppertiana. j 
“say in Buffalo before the American Association for 1876 by Professor W. J.. 
VOL. X.— No, 3, 12 
