PROLIFERATION. 



3 



developed a second cone above the first ; in correlation 

 with the production of the extra cone all the scales of 

 the lower one were sterile. 



A case in Cryptomeria japonica was seen in which a 

 proliferation from a female cone bore, a short distance 

 above it, male flowers. 



In the common primrose (Primula vulgaris) the axis 

 of the inflorescence is completely suppressed normally, 

 the individual flowers arising in the axils of the rosette- 

 leaves. But in the variety caulescens this axis becomes 

 developed, bearing the flowers either in a terminal 

 umbel* or more or less scattered along it. 



In those species, e. g. the cowslip (P. verts) and 

 P. obconica, whose inflorescence normally consists of a 

 simple umbel, proliferation may occur whereby one or 

 more supernumerary umbels may be formed (PI. 

 XXVI, figs. 1 and 2). In other species, e. g. P. japonica, 

 this structure is the normal one.f 



In proliferated spikes of the plantain (Plantago) the 

 main axis often becomes elongated much beyond its 

 normal height. 



Central or median proliferation of the flower-heads 

 ■or capitula of the Composite and other orders has from 

 time to time been seen. In view of the fact that these 

 heads represent extremely congested and shortened 

 spicate inflorescences it is not surprising if occasionally 

 the restraint of this extreme condition is, as it were, 

 swept aside, the axis extending its normally suppressed 

 internodes in order to form a fairly elongated structure, 

 This has been observed in the daisy (Bellis perennis), 

 in which a second capitulum was formed above the 

 first; and in Echinacea serotina central proliferation of 

 the secondary capitula occurring in the axils of the 

 involucral bracts has been observed. But in these cases 

 the capitula themselves do not appear to have been 

 changed in their constitution. Abnormal formation of 



* The "polyanthus" condition. 



f A good example of the widely-occurring phenomenon, first called attention 

 to by St. Hilaire, that what is abnormal in one species or genus may often 

 be the normal feature in an allied one. 



