256 BREEDING CROP PLANTS 



nucleus of Custard penetrated the ovary of Crookneck and took 

 up a position which, in many cases, was in close proximity to the 

 egg cell but for some reason fusion did not occur in most cases. 



Bailey (1890), as the result of many artificial pollinations, 

 concludes "that the field pumpkins and the summer and fall 

 types of bush squashes (C. pepo) do not cross with the running 

 squashes of the Hubbard, Marblehead, Boston Marrow, turban, 

 and mammoth types (C. maxima)." In the Cyclopedia of 

 American Horticulture, Bailey (1900) states that C. moschata 

 and C. pepo may be crossed artificially but it is doubtful if 

 they cross naturally. Cucurbitacece in general are monoecious 

 and largely dependent on insects for pollination. 



Immediate Effect of Pollination. There is a popular belief 

 widely disseminated that pumpkins and watermelons should 

 not be grown in close proximity to one another because of the 

 immediate effect of cross-pollination. A similar belief exists 

 with regard to cucumbers and muskmelons. Evidence accumu- 

 lated by various plant breeders shows that this idea is not founded 

 on fact. The work of Bailey at Cornell and Pammel at Iowa 

 may be cited. The former (1890) was unable to find any immedi- 

 ate effect of cross-pollination between varieties of C. pepo and 

 likewise between varieties of C. maxima. Bailey not only was 

 unable to demonstrate any immediate effect of pollen in varieties 

 which could be crossed but he was even unable to produce crosses 

 between cucumbers and muskmelons. Ninety-seven flowers of 

 several varieties of melons were pollinated with different varieties 

 of cucumbers. Not a single fruit set. Twenty-five reciprocal 

 pollinations were also made. One fruit developed but produced 

 no seed. The setting of parthenocarpic fruit without fertilization 

 is not an infrequent occurrence in cucumbers. Pammel (1892), 

 in an intermingled planting of varieties of each of the following 

 species, Citruttus vulgaris, Cucumis melo, Cucurbita maxima, 

 Cucumis sativus, and Cucurbita pepo provided excellent facilities 

 for inter-specific pollinations. Neither the watermelons nor the 

 muskmelons showed contamination. Some hand pollinations be- 

 tween species were made, but no cross-fertilization was obtained. 



The variability in flavor of commercial varieties of melons is 

 undoubtedly partly responsible for the erroneous belief that 

 they may be contaminated by other species of cucurbits grow- 

 ing in close proximity. At the Connecticut Station an extensive 

 varietal test was made. Most of the varieties were of 

 very inferior quality even though they were exposed only to 



