184 Rhodora [September 



i inch from the nearest adult of the species. It happens that all the 

 seedlings are up hill from the original bed, so that water could not 

 have furnished transportation. The arrangement of separating the 

 pockets by lines of stones and the peculiar position of the farthest 

 seedlings with reference to stones, exclude the garden rake as the dis- 

 persing agent. And finally, there are, within several miles of the 

 spot, no members of the species except those in the pocket mentioned, 

 so that the question of source is definitely settled. It seems clear, 

 then, that Viola rohmdifoUa has the power of casting its seeds to a 

 distance certainly of five, and very probably of nine, feet. 



The process of expulsion may be watched if the ripe, unopened 

 fruits are separated into their parts and laid on a table where they 

 will dry. Results will follow within a relatively short time, within a 

 few minutes if the capsules are already well prepared. In V, rotun- 

 dt/o/ia the middle of the three rows of seeds in each valve goes first. 

 Some of the seeds are merely pushed out. Many are thrown less 

 than a foot. Those that are caught in the right way between the 

 jaws of the machine, or have the strongest attachments to the placenta 

 fly the farthest. The intensity of the reaction is dependent largely 

 upon the tenacity of the seed-stalk, which parts and releases the pro- 

 jectile only after the lateral, or oblique, pressure has become consid- 

 erable. 



The round-leaved violet is one of the earliest to bloom. After 

 anthesis prostrate peduncles are put forth until past midsummer, 

 bearing cleistogamus flowers. The capsules lie on the ground, hid- 

 den away under the leaves and often more or less buried beneath 

 surface accumulations. When the performances of the earlier fruits 

 had been noted, the question was naturally suggested whether these 

 late pods have the same powers of projection, or whether owing to 

 lack of use, this power, like the sight of cave fishes, has been lost. 

 The answer was given at once, for all stages of the seed vessel from 

 imperfect ripeness to barren age were found together. That answer 

 is this. As the fruit approaches maturity the peduncle bends about 

 midway. The capsule is withdrawn from its seclusion and elevated 

 to a position about two inches above the earth, from which level the 

 valvular catapults may work with advantage. The seeds are then 

 expelled as in other cases. 



The Ames Botanical Laboratory, North Easton, Massachu- 

 setts. 



