348 STATE HORTICULTURAL SOCIETY. 



fruits are the same. This shows that the character or the vine is deter- 

 mined by the character of the seed from which it comes. My observa- 

 tion shows that this is invariably the case. 



There is no reason, therefore, to suppose that there is ever any imme- 

 diate effect of crossing in pumpkins and squashes.* 



2. Do pumpkins and squashes mix? — No one appears to doubt the 

 indiscriminate mixing of pumpkins and squashes. Before considering 

 the question, it is necessary to divide the fruits called squashes into two 

 groups. One group includes the summer and fall squashes, like the 

 scallops, common crooknecks, cocoanut, Bergen, and the like; these 

 belong to the same species as the field pumpkin, Cucurbita Pepo. These 

 squashes cross with the ordinary field pumpkin and with each other, 

 although the mixing even here does not appear to be indiscriminate. The 

 other group includes the Hubbard, Marblehead, turbans, and the so-called 

 mammoth squashes and pumpkins like Mammoth Chili and Valparaiso; 

 these belong to a distinct species, Cucurbita maxima. Many careful 

 pollinations have been made between these two classes of fruits, and in no 

 case have seeds been procured. Sometimes the fruit will develop for a 

 a time, and in two or three instances a summer crookneck pollinated by a 

 turban squash has developed until half grown, and has then persisted 

 until the end of the season, but it was seedless. All our experiments 

 show that Cucurbita Pepo and C. maxima do not hybridize. 



It is an easy matter to find fruits in any large assortment of pumpkins, 

 or summer squashes which might be taken for hybrids with the Hubbard 

 or turbans by a casual observer. ' But none of these fruits which have 

 come under my observation — and I have seen hundreds — possess any 

 marks of hybridity, and they have occurred in our experiments among 

 pedigree stock which had no Cucurbiia maxima blood in it. These so- 

 called hybrids are nothing more than incidental variations of Cucurbita 

 Pepo, and they may appear anywhere at any time. 



Our experience and observation show, therefore, that the field pumpkins 

 and the summer and the fall types of bush squashes do not mix with the 

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

 and mammoth types. 



3. Impotency of individual pollinations. — In pumpkins and squashes the 

 flowers are either wholly staminate or wholly pistillate, and they can not, 

 therefore, pollinate themselves. But the two kinds of flowers are 

 borne upon the same plant. Pollination between two flowers upon the 

 same plant I have termed individual pollination, in distinction from close 

 pollination, or pollination of the flower by itself, and from cross-pollina- 

 tion, or pollination between flowers on different plants. It has been 

 shown by Darwin and others that pollen is sometimes impotent upon the 

 pistil of the same flower, and I have been much interested, therefore, in 

 the relation of pollen to pistils upon the same plant in monoecious species 

 (those in which the sexes are borne in different flowers upon the same 

 plant). My attention was first called to this subject in 1889, when some 

 twenty or thirty* squash flowers were pollinated from flowers on the same 

 plant. A number of fruits grew to maturity, but they invariably pro- 

 duced poor seeds. This year the subject was carefully examined. One 



* The same observation can be made in reference to blackberries and raspberries. 

 Over 250 successful hand pollinations were made this year between blackberries, rasp- 

 berries, and dewberries in many combinations, and there were no immediate effects. 



