1922] ATWOOD—FORMALDEHY DE 237 
fall, and at 1-40 the germination was cut from 40-60 per cent, both 
in the blotters and in the soil. Here again, as in the previous 
series, the injury was greatest in the outdoor soil, less in soil indoors, 
and least of all in the blotter tests (figs. 3, 4). 
Formaldehyde readily forms various polymers (8, 25). On 
standing in the cool a flocculent white precipitate forms readily, 
[ec 
~ 
Beri 
90/—— nei 
~~. ae Ns el 
ag - 
OUTSIDE — a oe : 
i a en Panta” a 
To vo &. 
Pee ‘Sten 4 
a“ 
bf “> 
a 7 Pea 
s 
Ne- ia 
he 
70 
5H 
wv 
240 
MIN 0 30 120 
4 TIME 
Fic. 2.—Effect of time of soaking wheat on perentige Seaniaston, Turkey Red 
wheat from Moro, Oregon: solid li blotters, broken 
lines in soil serine and outside; formaldehyde mixed 1-3 20 parts of water; summary 
of 3600 seeds tes 
or on concentration of the commercial solutions. This is ordinarily 
referred to as paraformaldehyde, although the various polymers are 
probably often found more or less associated, and means for the 
identification of the various forms are not well known. Efforts 
have been expended toward developing methods to prevent such 
polymerization (28), but these methods have not been adopted in 
general. If wheat is dusted with the white flakes of this so-called 
paraformaldehyde, serious injury results. Turkey Red so treated 
