178 Rhodora [SEPTEMBER 
— both of these, however, were in the house, though the Poa was 
growing in earth. The true test would be to mark individual flowers 
in natural conditions out of doors — paint, or waterproof ink might be 
used. 
Poa annua is a grass always “on tap.” I found the first open flower 
this year (1912) on April 28, and it will keep in bloom until late fall, 
and then may be potted and will flower through the winter in the house, 
while as to time of day, I have found blossoms open out of doors from 
3 A. M. (before light) to 6 P. M.! 
One often finds grass flowers open and not a grain of pollen left in 
the anthers, which then usually resemble two empty canoes placed 
back to back. Grasses are wind-fertilized, and Hackel states that 
they are “usually protandrous, more rarely protogynous (Alopecurus, 
Anthoxanthum, Spartina)” “The anthers empty most of the pollen 
at once by turning completely over; when the stigmas project later- 
ally from the pendulous or nodding spikelet they turn upward, and 
thus are only dusted with the pollen of flowers situated above. Rarely 
they project from the tip of the spikelet. This occurs in protogynous 
or monoecious species. ‘The glumes in species of Alopecurus, Antho- 
xanthum, Phalaris and Phleum open scarcely or not at all during 
anthesis. In these cases, stigmas and anthers project through a 
narrow slit." 
If I had read the above at the beginning of the summer, it would 
have saved me many fruitless efforts to find open flowers of PAleum. 
Neither did I find any in Spartina, but I found anthers shedding pollen 
in abundance out of doors, at 10.30 A. M. on a sunny day, and once, 
bringing a dew-soaked inflorescence into the house at 6 A. M., it shook 
out the pollen at 10, when the dew had dried. 
But the most drenching dew does not seem to hinder the pollen of 
Ammophila arenaria from flying in thick clouds: I found it thus on 
Aug. 23 at 6.15 a. M. An hour later, returning from my walk, I 
found the usually trim, terete inflorescence looking positively ragged 
with the many gaping mouths of the flowers up and down the spikes, 
the pollen not being all shed, though examining spikes as late as 
9 4. M. I found the anthers quite empty. A quotation given by Kunth 
says “the stigmatic branches do not protrude, and are receptive within 
1 But it flowers most profusely in the early morning — one day in June, at 5 A. M., 
I counted, on the panicles borne by one root of Poa annua, 30 open flowers, there being 
usually two in the same spikelet. 
