88 Dr. H. Karsten on the Seosual Life of 



Still, the propensity to credit what is marvellous, and to ex- 

 cite an interest by taking up the defence of bold hypotheses at 

 variance with hitherto acknowledged laws, did not allow the 

 results arrived at by the united assiduous labours of so many 

 naturalists to go unchallenged. 



For instance, a report made by Smith, in 1841, that he had 

 noticed in the Cmlebogyne grown in Kew Gardens no male 

 flowers, and that, notwithstanding this, the plant produced fer- 

 tile seeds, induced Naudin to repeat Spallanzani^s experiments 

 on Cannabis and Mercurialis ; and from the origination of fertile 

 seeds in isolated female specimens of those two plants, as well 

 as in a female Bryonia dioica grown in the open air, he felt himself 

 entitled to deny that the fructification of the ovules of plants is 

 necessary to the development of normal germs. 



Radlkofer, prompted by the observations of Siebold (1857- 

 1858) respecting the capacity of development of the unim- 

 pregnated eggs of bees and moths, made use of these state- 

 ments of Naudin to construct his hypothesis of the partheno- 

 genesis of plants ; but, at the same time, he omitted to notice 

 that the normal formation of buds and the development of ovules, 

 occurring in an abnormal manner analogous to the production of 

 buds, ai'c long- and well-known phenomena, corresponding like- 

 wise with the production of living progeny by the Aphides and 

 Trematoda, and with that of barren eggs by insects. 



Under the influence of his preconceived ideas he has failed to 

 note that the researches of Naudin were instituted on polygamous 

 plants, — a circumstance which naturally suggests to the mind 

 that a concealed male flower, or an anther produced in the in- 

 terior of a female flower, may have led the obsei-vcr into error. 



The observations of Smith on Coelebogyne apj)eared to Radl- 

 kofer's mind to supply ample evidence in favour of his notion of 

 vegetable parthenogenesis. Some examinations were undertaken 

 by him on the Coelebogyne and its embryos during a visit to Kew, 

 in the course of which he once detected a pollen-cell on the 

 stigma; this occurrence, however, failed to shake his faith in 

 the conclusion he had already arrived at. 



The same fortune that befell Radlkofer also attended Braun, 

 who in the same year got Deeke to examine the embryos of the 

 Ccelebogyne cultivated in the Botanical Gardens of Berlin. For 

 although Deeke showed that there is a normal act of fertilization 

 of the germ-vesicles in the embryo-sac of Coelebogyne, yet Braun 

 considered himself justified in propounding to the Berlin Aca- 

 demy his ideas of parthenogenesis in plants. Braun further 

 supported this hypothesis by appealing to the before-quoted re- 

 searches of Henschel and earlier inquirers, and to the circumstance 

 of the much rarer existence of male specimens of Chara crinita, 



