78 BOTANICAL GAZETTE [JANUARY 
the kernels at maturity. The effect is not due to shock injury, for it does not 
manifest itself until at least a week after removal. The rachis of the clipped 
spikes contains about 25 per cent more ash than the unclipped. This is 
probably due to the fact that the awn when present is a great ash storage 
organ. The high ash content of the rachis probably accounts for the marked 
shattering in the clipped heads. The authors say: “Hooded and awnless 
barleys generally yield less and shatter more than awned varieties, and there 
seem to be physiological reasons for this fact.” It may be possible to produce 
non-shattering hooded and awnless sorts by using parents which normally 
have a low percentage of ash in the rachises. It may also be possible to 
obtain strains that will give good yields under arid conditions. Under humid 
conditions it is likely that the objections to the awns are more easily met by 
the use of strains with smooth awns, which, so far as known at present, have 
no physiological limitations —WM. CROCKER. 
A subterranean algal flora——Moore and Karrer’ have demonstrated 
the existence of a subterranean algal flora, independent of the terrestrial flora 
and to a great degree of the character and locality of the soil. The investi- 
gation included an analysis of a variety of soils collected in Missouri, California, 
and Massachusetts. The samples were collected at different depths under 
sterile conditions and in localities where the soil had not been disturbed for a 
number of years. These were placed in bottles containing an amount of 
sterile algal nutrient solution and sterile sand. The growth was examined 
at the end of several weeks, and in this manner the algae which occurred in 
small amounts could easily be studied. From these investigations it was 
shown that algae exist in the soil to a depth of 1 m. at least under conditions 
which preclude the possibility of surface infection. A wide variety of species 
(Kiitzing) occurred at all depths and in all the samples obtained in the widely 
separated localities JOANNE KARRER. 
Odor constituents of apples.—PowerR and Curstnut® have found that 
the odor constituents of apples consist essentially of amylesters of formic, 
acetic, and capsoic acids, with a very small amount of caprylic ester and a 
considerable proportion of acetaldehyde. The acids mentioned are probably 
present also in the free state. These essential oils constitute only about 
© .0007-0.0013 of 1 per cent of the weight of the entire ripe fruit. ‘‘ Although 
amyl valerate is generally designated in chemical literature as ‘apple oil,’ it is 
quite certain that this compound has never been identified as a constituent of 
apples.” The difference in odor of various apples is due to the difference in 
proportions of the oils mentioned.—W. CROCKER. 
7 Moore, G. T., and KAarrer, JOANNE L., A subterranean algal flora. Ann. Mo. 
Bot. Gard. 62281-4307. IgI9Q. 
8 Power, F. B., and CHESTN Nut, V. K., The odorous constituents of aye 
anne of scciskictons from the ripe fruit. Jour. Amer. Chem. Soc. 42 
1526. I 
