EEPOItT OX VEGETABLE PA IITH ENi >G ENESIS. lol 



" previous influence of pollen, and consequently a true partheno- 

 " genesis exists." 



Further on, Dr. Braun alludes to the la.-t of ihc persistence of 

 the stigma (upon which, as wo have mentioned, ioidlkofcr relie 

 showing tlie absence of impregnation. In Cryptogams a remarkable 

 instance of apparent part heimiiyncsis occurs in CJtara crinitq. in all 

 the Characeic, with the exception ol'lliisi species, the male an<l female 

 Organs are equally common, sometimes on the same, sometimes on 

 separate plants. After noticing the distinctive feat arcs of the sp< 

 its geographical distribution, and the certainty that in many localities 

 the female plant alone exists, Dr. Braun gives it as nis opinion that, 

 at least in certain places, Chara crinlta has the capacity of prodm-mir, 

 without the operation of any male organ, normal spores capable of 

 germination, and consequently that it affords an instance of veritable 

 parthenogenesis. 



In ' Bonplandia,' for 1857 (p. 209), Klotzsch suggested that the 

 so-called embryo in Coelebogyne is in fact not an embryo at all. He 

 says that all the Euphorbiacere, without exception, have anatropal 

 ovules, and a highly developed straight embryo with the radicle turned 

 to the micropyle, whilst the large flat cotyledons winch enclose the 

 plumule are directed to the chalaza. In Coelebogyne, on the contrary, 

 no freely developed embryo is perceptible, nor is there any trace of 

 a radicle turned towards the micropyle, or of cotyledons turned 

 towards the chalaza, Instead of the above, there is found an ellip- 

 tical body within a fleshy, not albuminous, envelope, and consisting 

 of a convoluted leaf -like mass, firmly attached on the inside of the 

 seed to the chalaza by a discoid foot. From these facts Klotzsch 

 arrives at the conclusion that the supposed embryo is a bud formed 

 within the seed. 



Eupreclit* has objected that Klotzsch has given no figure of the 

 perfect seed, and without this he seems to consider Klotzsch's ob- 

 servations open to doubt, at the same time expressing no opinion 

 either for or against parthenogenesis. 



Radlkofer's second essay on parthenogenesis relates to some 

 matters of opinion in dispute between himself and Braun. He dis- 

 cusses the nature of the germinal vesicle before impregnation, and 

 considers that in that stage it must be looked upon, not as the germ 

 of the future plant, but as a rudimentary bod)- capable of becoming 

 a germ; a distinction somewhat subtle, and not very easily appre- 

 ciable. He also enters upon the question of the analogy between 

 the embryo-sac and the spore of the higher cryptogams. These 

 matters, however, have no bearing upon the practical question 

 as to the existence or non-existence of parthenogenesis in vegeta- 

 bles, and we refrain therefore from any further details with regard 

 to them. 



In 1859, Hegel's paper, " Die Parthenogenesis im pfl^ze^-refche," 



* Em Beitrair zur Fi\i,q-c iilicr die Parthenogenesis bei Pilauzen, iin Bulletin dc 

 l'Acad. Imp. dcS. Peterebourg, 1858, p. -274 ; No. 378. 



