1917] BRIEFER ARTICLES 167 
and germinated as quickly and apparently with as much energy as fresh 
seeds. Of the original 100 seeds 24 still remain intact. 
In order to ascertain the resisting power of the seed coats of velvet 
leaf to water at various temperatures, in December 1916 I collected 
seeds from plants still standing in the field. | Most of the seeds at that 
time had dropped from the pods, and those I found were mostly hard- 
coated. In one case only 3 seeds in 100 had swollen after soaking 
48 hours at room temperature. Two lots of seeds of 100 each were 
selected and each lot was placed in a small vial. The vials were then 
filled with water at a given temperature and suspended in Dewar flasks 
filled with water at the same temperature. At the end of 6 hours the 
vials were removed, the seeds that had swollen were counted, removed, 
and the naire seeds were returned for a similar period at a tem- 
perature 5° higher, and so on until all the seeds had swollen. The tem- 
perature of the flask for each period was kept practically constant. 
The seeds in flask no. 1 were started at 30°C., and in no. 2 at 35°C. 
The results are indicated in table I. 
TABLE I 
FLASK NO. I Fiasx No. 2* 
Tempera- | Ti Number ~| Ti Number 
Re er |) ee Pe eee ee 
ac. 6 8 35 C... 6 e S 
5 eee 6 9 Se 6 oo ae 
4° Ce 6 Ig Ce * 6 12 : 
6525-5 6 se es ee 6 as oe 
oo 6 8 (Cage 6 13 
See.0 lS, 6 cs eae 6 9 
60... 6 12 G6. ..2 6 to 
6§... 6 7 eee 6 oS 
2 6 iS § ys. 6 4 
75: tye es 6 5. oe 
= _Tesistant may lie i in the soil many years 1s befo 
—Wier E. D, Kan 
