No. 640] VARIATION AND HEREDITY IN LUPIXUS 441 



age of swelling was 95 per cent, or better except in two 

 cases, each of which had only 40 per cent, of the seeds 

 swelled. The remaining lots averaged 51 per cent, of 

 sprouted seeds. Two gave 100 per cent., one gave 95 

 per cent, and 14 were below 25 per cent. 



From these results it appears that many seeds which 

 show no observable defects are nevertheless either dead 

 or in a state of dormancy not readily overcome. That 

 the latter is probably the true explanation is indicated 

 by the fact that more seeds treated in this manner actu- 

 ally sprout than when the seed coats are mechanically 

 ruptured. The treatment with the acid seems to act in 

 some manner, possibly by dehydration, as a slight stimu- 

 lant to sprouting. It is not certain, however, that a 

 larger percentage of viable seedlings is actually produced. 

 Many seeds put forth the radicle in an apparently normal 

 manner, but do not continue growth. Others die at later 

 seedling stages apparently from internal causes, for they 

 have not had opportunity of infection and are growing 

 under the same conditions as others in the same culture. 



This spring and winter a number of cultures were tried 

 in which the seed were treated with acid, washed, and 

 then planted directly in the soil out of doors. In every 

 case a good stand was secured averaging about 50 per 

 cent, of the seeds planted. The seedlings of the preceding 

 season were planted in pots and kept in the greenhouse 

 until a vigorous young plant was secured, and then trans- 

 planted to the garden. They did very poorly after being 

 transplanted and produced practically no seed. It is 

 uncertain whether the failure was due to faulty technique 

 in transplanting or to the failure of the plant to adapt 

 itself to the change of environment. It is not unlikely 

 that both causes had something to do with the matter. 

 They had been grown in 5-in. pots and transplanted with 

 the whole mass of dirt, but even in that w^ay some dis- 

 turbance of the root system was unavoidable. In addi- 

 tion to this there was a very hot, dry wind lasting three 

 days about flowering time. This seemed to do a lot of 



