15}4 PROCEEDINGS OF THE ACADEMY OF [1897. 



HYBRIDS IN NATURE. 



Our gardens abound with hybrid plants. Although the garden- 

 er's skill originates them, there seems little reason why they should 

 not occur in nature. The plant desired to produce seed has its flower 

 opened by the hybridizer before it naturally expands ; the anthers 

 are removed before the pollen-sacs are ruptured, insects are ex- 

 cluded, and the next day probably, when the stigma is receptive, 

 the foreign pollen is applied. In this way hybrids are secured. 

 From the ease with which hybrids are produced in this way arises 

 the belief that hybridism in nature must be of frequent occurrence. 



It is a matter of grave importance that we decide how far this 

 belief is correct. Up to a period not remote, it was a belief that 

 what we know as a species was always a species from the earliest 

 epoch. When a distinct form came under observation that seemed 

 not to have existed from the beginning, it was regarded as a hybrid. 

 It would be accepted as a species, though deemed of hybrid origin. 

 Thus Linna?an nomenclature abounds in " hybrxda " as a specific 

 denomination. If it can be shown that these are not hybrids, but 

 have been evolved from other species under some regular law of de- 

 velopment, the importance of the question becomes apparent. 



We now accept the doctrine of evolution as beyond discussion. 

 Species do follow from other species as the world advances; but the 

 old idea is still so prevalent, that many botanists who accept the 

 tacts of evolution in a general sense are very apt to regard any un- 

 usual departure as a case of hybridism. Our modern literature 

 abounds in such instances. Supposed hybrids are being continually 

 described as actual hybrids on no other grouud than that they pos- 

 sess characters common to others already described. 



If nature intended hybrid! ty to be one of her handmaidens in 

 the production of new forms, she has strikingly failed. Let us 

 take the oak as an illustration. When the male flowers are at a 

 certain stage, a slight jarring of a branch will cause the pollen to 

 float away in little clouds discernible to the watchful eye. One may 

 readily conceive what an enormous quantity of pollen must be car- 

 ried from one tree to another by every sudden breeze. In our 

 v, ds there are rarely less than two or three species in company. 

 Not infrequently there are more, and these are usually blossoming 

 all at one time. Hypothetically, one may argue that these gregar- 

 ious species must receive one another's pollen, must cross-fertilize, 

 must result in a hybrid progeny in which every separate character- 



