524 BOTANICAL GAZETTE [December 



some asparagus growers in California, who testified that there was 

 a greater percentage of fasciated shoots in their beds of asparagus 

 during the period when the first stems pierce the soil, especially 

 after a cold winter. 



DeVries conducted experiments 2 in his garden at Amsterdam, 

 and minutely studied fasciated plants in their natural conditions. 

 From the experiments and observations he agrees heartily with 

 Goebel that fasciation is due to internal stimuli, notably increasing 

 pressure of cell sap. 



The whole question of monstrosities might be ignored but for 

 the light their study throws upon numerous morphological struc- 

 tures among plants. To illustrate some of these morphological 

 problems the lists of floral parts which are closely united have been 

 cited . In the whorl of microsporophylls one often finds a complete 

 union of the filaments, also the fusion of megasporophylls in the 

 formation of compound ovaries; the fusion of the petals in the 

 gamopetalous corolla, as for instance in the orchids; the fusion of 

 seed coats in cycads; the fusion of nucellus and integuments in 

 some of the other gymnosperms; the fusion of the bract with the 

 axillary flowering stock in basswood (Tilia americana); and the 

 union of the calyx with the ovary as in the apple and other po- 

 maceous fruits. This group of morphological modifications was 

 classified as negative by Worsdell, 3 The same author classifies 

 as positive congenital increase of parts the following: the pappus 

 or the sepals in the Compositae; twin embryos which develop 

 from a single egg that divides vertically perhaps instead of trans- 

 versely; and twin flowers which arise by the modifications of the 

 apical region of growth. 



Worsdell holds that, in addition to these congenital fusion 

 problems, there are those which may be called post-genital; for 

 example, the plantain with twin spikes of flowers at the summit of 

 the stem, the Campanula with four flowers borne at the apex of 

 an abnormal stem, the leaves of the Oxalis sometimes individual 

 instead of being in three parts as is customary, the fusion of the 

 flowers in Crocus, and lastly fasciation itself. In support of his 

 view that the various monstrosities in plants are sometimes con- 



3 Die Mutationtheorie 2:541. 1903. * New Phytol. 4:55-74. i9°5- 



