122 Gardening 
New Jersey Expt. Sta. 
Fic. 73. Three new varieties of squashes produced by crossing a white scallop 
summer squash (P, at the left side of picture) with a warty, yellow-colored sum- 
mer crookneck (P, at right side). The photograph shows three new varieties 
that have been produced. The upper row shows a type of short-necked “‘jug”’ 
fruit of medium size with a smooth, cream-colored surface. The middle row 
shows a longer-necked type of “jug” fruit, somewhat like the crookneck in shape, 
but green-striped and not warty. In the lower row the fruits are very thin- 
fleshed, nearly spherical, cream-colored, and not warty. After the first crossing, 
the plants were selected and self-bred for five generations, after which some of 
the new kinds would breed true enough to make new varieties. 
shape, size, color, and quality of flesh. Selection and 
breeding of these hybrids will develop new varieties 
(Fig. 73). 
New varieties are usually first described in the seed 
catalogues as “novelties.” In the course of time 
novelties may become standard varieties, or they may be 
discarded because they prove unworthy of cultivation. 
How the plant breeder works. In cross-breeding 
plants, the breeder needs to know for a certainty what 
the parents are. He, therefore, first selects the two 
plants that he wishes to cross. Then he applies the 
pollen from one of them to the pistil of one or more 
flowers on the other. To prevent self-pollination or 
stray cross-pollination he may remove the stamens from 
the flower that is to be pollinated, cover it with a paper 
bag, or carry out such other measures as may be neces-— 
