342 



lomorphosis) the organ also approaches the foUage leaf in form. Bracts 

 become normal stem leaves, the sepals are replaced by actual foliage leaves, 

 the petals become green and fleshy, the pistils become stamens (staminody) 

 or the stamens and pistils assume the character of petals or green, fleshy 

 leaf-like structures, as, for example, in the double cherry, the double 

 Ranunculus, etc. In mignonette, through phyllody of the ovules, little leafy 

 axes can be formed in the urn-like open ovule cases. In the favorite tub- 

 erous Begonias, I found that the placentae had grown out of the ovule cases 

 and the ovules carried over on to petal-like transformed branches of the 

 pistil, etc. 



There are cases in which all the parts of a flower are transformed into 

 small, uniformly green leaves, i. e., a complete green flozver condition 

 (chloranthy) arises. One of the best exam.ples of this is the green rose 

 {Rosa chinensis, Jaqu.), received in its time with great enthusiasm, the 

 transformation processes in which have been thoroughly described by 

 Celakowsky\ 



I would like to introduce here also parthcnogensis, which various 

 scientists have often proved recently to be of constant occurrence. Kirchner- 

 saw in this an arrangement "which, differing from the much more wide- 

 spread, spontaneous self-pollination, serves to assure the development of 

 seed, capable of germination, in cases where, for any reason whatever 

 pollination has become uncertain or difficult." Even those seed primordia 

 can be assumed to be of a somatic character, in which, at the time of the 

 production of the embryo sacs, the reducing division is suppressed and the 

 egg cell retains a vegetative character. 



In cryptogamic plants Apogamy corresponds to the process of phyllody 

 in the phanerogams. Instead of the sexual products, vegetative organs 

 appear here, as in Athyrium Filix feniina var. cristatum^ Aspidium falcatum 

 and Pteris cretica. It is said that in the last plant, no more female sexual 

 organs are formed at all, but the young plant is produced from a vegetative 

 sprout exactly on the places in the prothallium, where the archegonia must 

 have stood'. 



Such plants which "produce their young alive" (viviparous) furnish 

 abundant material for propagation, just as, for example, the bulblets of 

 many lilies, produced by the transformation of a flower. 



The Barrenness of the Hop. 



A special process of phyllody, of great agricultural significance, is the 

 barrenness, the blindness, the fool's head formation of the hop. The names 

 designate only different degrees of a malformation which begins with a 

 simple, abnormal lengthening of the catkins and develops into the formation 



1 Celakowsky, Beitrage zur morphologischen Deutung des Staubgefafses. 

 Pringsheims Jahrb. 1878, p. 124. 



-• Kirchner, O., Parthenogenesis bei Bliitenpflanzen. Ber. d. Deutsch. Bot. Ges. 

 1904, Vol. XXII. Generalversamnilungsheft. Here also a bibliography. 



a Noll in Straszburger's Lehrbuch der Bot. 1894, p. 243. 



