By Thomas Andrew Knight, Esq. 371 



ever, heard it asserted, that female rnule birds have been 

 known to breed under similar circumstances ; that is, with 

 a male of the same species as the male parent of the mule ; 

 but upon trying the experiment, it did not at all succeed in 

 my hands. The mule birds laid eggs, apparently well orga- 

 nised, upon which they sat; but the eggs soon became 

 putrid ; and I had good reason to believe, that the first 

 pulse of life had never beaten in any of them. 



If hybrid plants had been formed as abundantly as Lin- 

 NiEus and some of his followers have imagined, and such had 

 proved capable of atTording offspring, all traces of genus 

 and species must surely, long ago have been lost and obli- 

 terated ; for the seed vessel even of a monogynous blossom 

 often affords plants which are obviously the offspring of dif- 

 ferent male parents; and I believe I could adduce many facts, 

 which would satisfactorily prove, that a single plant is often 

 the offspring of more than one, and, in some instances, of 

 many male parents. Under such circumstances every spe- 

 cies of plant which, cither in a natural state, or cultivated by 

 man, has been once made to sport in varieties, must almost 

 of necessity continue to assume variations of form. Some of 

 these have often been found to resemble other species of the 

 same genus, or other varieties of the same species, and of 

 permanent habits, which were assumed to be species ; but I 

 have never yet seen a hybrid plant, capable of affording off- 

 spring, which had been proved, by any thing like satisfac- 

 tory evidence, to have sprung from two originally distinct 

 species; and I must therefore continue to believe, that no 

 species capable of propagating offspring, either of plant or 



