188 



PRINCIPLES OF PLANT-TERATOLOGY. 



cerned. This also is the most likely explanation of the 

 antheriferons and ovuliferous foliage-leaves of Gi'ngko. 



8. Bracteody of Scale-leaves.— Under this heading 

 must be placed the curious abnormality which Wilhelm 

 observed in the spruce in which the apex of a vegeta- 

 tive shoot became transformed into a cone ; in such a 

 case two main changes are implied, viz., excessive 

 shortening of the axis, and transformation of scale- 

 leaves into bracts. 



9. Sepalody of Bracts. — In the wood-anemone 

 (Anemone nemorosa) and in several other species the 

 foliaceous bracts may, one or other of them, assume 



the form and colour of the 

 sepals. Such a case as this 

 reminds one of those normal 

 instances where bracts are 

 always brightly coloured, as in 

 Bromeliacese, Poinsettia, etc. 

 10. Stamjnody of Bracts. — 



igra. Bracts The " bract " (" DecksdlUppe " 



of lower part of cone changed of the Germans) which subtends 

 To^ZZZ^X^ and ^PPorts the "seminiferous 

 part of cone normal. scale " in most ConiferaB, has 



been variously interpreted as a 

 true bract or as a carpel. In proliferated cones, e.g. in 

 Larix eurojjdea and Picea nigra, transitions have been ob- 

 served between this " bract " and stamens, the extreme 

 modified form of the organ bearing pollen-sacs on its 

 dorsal side (tig. 50). This phenomenon, of course, does 

 not decide either way as to the morphology of the 

 organ. Its bract-nature, however, being convincing, its 

 consideration is included here. It is this phenomenon 

 which gives rise to the hermaphrodite cones. Usually 

 these modified " bracts " occur in the lower region of 

 the cone. Keissler observed an androgynous cone of 

 the spruce in which a similar change had taken place 

 in the upper part of the "inflorescence," thus remind- 

 ing one of the usual condition in the " flower " of 

 Selaginella in Avhich male sporophylls occur in the 



