Chap. XXVI. RELATIVE POSITION OF PARTS. 347 



fact, that some florists regularly pinch off the central trusses of flowers. 

 Whether in the highly improved varieties the departure of the central 

 trusses from their proper type is due to reversion, 1 do not know. Mr. 

 Dombrain insists that, whatever may be the commonest kind of imper- 

 fection in each variety, this is generally exaggerated in the central truss. 

 Thus one variety " sometimes has the fault of producing a little green 

 " floret in the centre of the flower," and in central blooms these become 

 excessive in size. In some central blooms, sent to me by Mr. Dombrain, 

 all the organs of the flower were rudimentary in structure, of minute size, 

 and of a green colour, so that by a little further change all would have 

 been converted into small leaves. In this case we clearly see a ten- 

 dency to prolification— a term which, I may explain to those who have 

 never attended to botany, means the production of a branch or flower, 

 or head of flowers, out of another flower. Now Dr. Masters 24 states that 

 the central or uppermost flower on a plant is generally the most liable to 

 prolification. Thus, in the varieties of the Auricula, the loss of their 

 proper character and a tendency to prolification, and in other plants a ten- 

 dency to prolification and pelorism, are all connected together, and are due 

 either to arrested development, or to reversion to a former condition. 



The following is a more interesting case; Metzger 25 cultivated in Ger- 

 many several kinds of maize brought from the hotter parts of America, 

 and he found, as has been previously described, that in two or three 

 generations the grains became greatly changed in form, size, and colour ; 

 and with respect to two races he expressly states that in the first genera- 

 tion, whilst the lower grains on each head retained their proper character, 

 the uppermost grains already began to assume that character which in 

 the third generation all the grains acquired. As we do not know the 

 aboriginal parent of the maize, we cannot tell whether these changes are 

 in any way connected with reversion. 



In the two following cases, reversion, as influenced by the position of 

 the seed in the capsule, evidently acts. The Blue Imperial pea is the 

 offspring of the Blue Prussian, and has larger seed and broader pods 

 than its parent. Now Mr. Masters, of Canterbury, a careful observer and 

 a raiser of new varieties of the pea, states 26 that the Blue Imperial always 

 has a strong tendency to revert to its parent-stock, and the reversion 

 " occurs in this manner : the last (or uppermost) pea in the pod is fre- 

 " quently much smaller than the rest ; and if these small peas are care- 

 " fully collected and sown separately, very many more, in proportion, 

 " will revert to their origin, than those taken from the other parts of the 

 " pod." Again M. Chate^says that in raising seedling stocks he succeeds 

 in getting eighty per cent, to bear double flowers, by leaving only a few of 

 the secondary branches to seed ; but in addition to this, " at the time 

 " of extracting the seeds, the upper portion of the pod is separated and 



24 ' Transact. Linn. Soc.,' vol. xxiii. 26 ' Gardener's Chronicle,' 1850, p. 

 1861, p. 360. 198. 



25 ' Die Getreidearten,' 1843, s. 208, 2 " Quoted in ' Gardener's Chron.,' 

 209. 18G6, p. 74. 



