No. 4.] CROSSING OF PLANTS. 47 



greater strength or virility makes the stronger impression 

 upon the hybrids, whether it is the staminate or pistillate 

 parent. And it appears to be equally true that it is usually im- 

 possible to determine beforehand which parent is the stronger. 

 It is certain that strength does not lie in size, neither in the 

 high development of any character. It appears to be more 

 particularly associated with what we call fixity or stability 

 of character, or the tendency towards invariability. This has 

 been well illustrated in my own experiments with squashes, 

 gourds and pumpkins. The common little pear-shaped gourd 

 will impress itself more strongly upon crosses than any of 

 the edible squashes and pumpkins with which it will effect 

 a cross, whether it is used as male or female parent. Even 

 the imposing and ubiquitous great field pumpkin, which 

 every New Englander associates with pies, is overpowered 

 by the little gourd. • Seeds from a large and sleek pumpkin 

 which had been fertilized by gourd pollen produced gourds 

 and small hard-shelled globular fruits which were entirely 

 inedible. A more interesting experiment has been made 

 between the handsome green-striped Bergen fall squash and 

 the little pear gourd. Several flowers of the gourd were 

 pollinated by the Bergen in 1889. The fruits raised from 

 these seeds in 1890 were remarkably gourd-like. Some of 

 these crosses were pollinated again in 1890 by the Bergen, 

 and the seeds were sown in 1891. Here, then, were crosses 

 into which the gourd had gone once and the Bergen twice, 

 and both the parents are to all appearances equally fixed, the 

 difference in strength, if any, attaching rather to the Bergen. 

 Now, the crop of 1891 still carried pronounced characters of 

 the gourd. Even in the fruits which most resembled the 

 Bergen the shells were almost flinty hard, and the flesh, even 

 when thick and tender, was bitter. Some of the fruits 

 looked so much like the Bergen that I was led to think that 

 the gourd had largely disappeared. The very hard but thin 

 paper-like shell which the gourd had laid over the thick yel- 

 low flesh of the Bergen, I thought might serve a useful pur- 

 pose, and make the squash a better keeper. And I found 

 that it was a great protection, for the squash could stand any 

 amount of rough handling, and was even not injured by ten 

 degrees of frost. All this was an acquisition, and, as the 



