1880. ] : Botany. 127 
his plunges to get at the nectar, but left the plant after trying a 
single flower. In frequent visits he often saw humming birds 
about the flowers going to all that were open at the time. Ever 
time the birds thrust their beaks into the flowers, if the stamens 
had not yet been removed, the head, a little above the beak, 
would hit these and become dusted with pollen. Where the 
anthers had been removed the birds head left pollen on the stig- 
mas. He saw, in one cluster, all the flowers visited twice in fif- 
teen minutes. He is confident that /impatiens fulva is cross-fer- 
tilized mainly, if not wholly by humming birds. 
CONNECTION OF THE RAINFALL WITH Forests.—According toa 
paper in Fol/yéiblion, the following are the laws of meteorology as 
affected by forests:—1. It rains more abundantly, under identical 
circumstances, over forests than over non-wooded ground, and most 
abundantly over forests with trees ina green condition. 2. The de- 
gree of saturation of the air by moisture is greater above forests than 
over non-wooded ground, and much greater over masses of Pinus 
sylvestris than over masses of leaved species. 3. The leafage 
and branches of leafed trees intercept one-third, and those of 
resinous trees the half of the rainwater, which afterwards returns 
to the atmosphere by evaporation. On the other-hand, these same 
leaves and branches restrain the evaporation of the water which 
reaches the ground, and that evaporation is nearly four times less 
under a mass of leafed forest than in the open, and two and one- 
third times only under a mass of pines. 4. The laws of the change 
of temperature out of and under wood are similar so those which | 
result from the observations of M. Mathieu. The general con- 
clusion seems to be that forests regulate the function of water, 
and exercise on the temperature, as on the atmosphere, an effect 
of “ ponderation” and equilibrium.—4nglish Mechanic. : 
Tue New Mexican Locust Tree, ETc.—In the article on Col- — 
orado plants in the November number, on page 681,inthe note on _ | 
Salix flavescens, the word “hybrid” should read “form.” Itis 
apparent that no “hybrid” can occur unless both parents are- 
found in the same vicinity, which in this instance is not the case. 
Saxifraga chrysantha from Pike’s Peak is apparently the same as _ 
S. serpyllifolia of Porter and Coulter's Catalogue. Artemesia _ 
arctica, Cnicus edulis and Troximon glaucum are referred to, the 
last two under other names. Robinia Neomexicana is described 
therein also. E. L. Green, who first collected this species in — 
Colorado, furnishes me with some interesting facts regarding it, 
which I take the liberty to quote from his letter. “The clump 
to-day the only known habitat of the species north of New 
Mexico, and strange to say, those trees are twice as large as an 
ever saw in New Mexico; right on the banks of the river, a 
all around that clump of locusts grows Bigelovia greenet, whic: 
of trees to which you refer was found by me in 1873. eee 2 
