Allgemeines. 291 



Chittenden, F. J., The influence of the Parents on the Colour 

 of the Hybrid, (p. 213—217.) 



Taking a very miscellaneous list of hybrid plants the author 

 finds 42 following the poUen parent mostly; 46 following the seed 

 parent mostly; 92 nearly intermediate; and 3 following neither, as 

 regards the colour of the flowers. 



Pfitzer, Prof., Hybridisation and the systematic arrange- 

 ment of Orchids. (p. 218—221.) 



The author finds the general evidence of hybridisation to speak 

 somewhat for his own systematic arrangement and against that of 

 Bentham. In certain cases as in that of a supposed cross between 

 Odontoglosstnn and Zygopetahmt , it is suggested that the Odonto- 

 glossiim pollen had sufificient influence to stimulate the Zygopetalunt 

 into producing an embryo, but without impressing any of its own 

 characters, since the supposed hybrids exactty resembled the Zygo- 

 petahun parent, whilst at the same time it is very difficult to suppose 

 that the pollen of Zygopetalum was not properly excluded. 

 Rolfe, R. A., Natural hybrids of the Cattleya group. (p. 

 222—241.) 



Natural hybrids have been recorded from forty species of this 

 genus, a füll list is given with references to the principal descriptions 

 and figures. 

 Crawshay, de Barri, Hybrid Odontoglossa. (p. 242 — 272.) 



A profusely illustrated account of hybrids in this genus. 

 Tsehermak, ü., The importance of Hybridisation in the 



study of Descent. (p. 278—284.) 

 Ostenfeldt, C. H., Castration and Hybridisation in the Genus 

 Hieracium. (p. 285—288.) 



Among 15 species of the subgenus Archieraciuni , only one 

 H. iintbellatmn was found to need fertilisation , all the others giving 

 abundant fruits after castration. In the subgenus Stenotheca on the 

 other band both the species examined seem to require fertilisation. 

 H\'brids were obtained by crossing H. excellens with H. \piIosella and 

 H. auvantiaciun. The sister hybrids differ among themselves, but 

 they inherit the power of producing ripe fruits without fertilisation. 

 Rosenberg, O., Cytological Investigations in Plant Hybrids. 

 (p. 289—291.) 



A summar}^ of observations on the cytology of the hybrid between 

 Drosera longifolia and D. rotiuidifolia. 

 Bernard, N., On the Germination of Orchids. (p. 292—296.) 



Orchids were found te require the presence of certain fungi for 

 their germination. The number of species of these fungi is probably 

 ver}" much smaller than the number of species of orchids. The 

 "virulence" of the fungi varies according to their origin and age. 

 It is sometimes possible to raise an orchid with the fungus properly 

 belonging to a different species, the seedlings so obtained frequently 

 differ a little from those cultivated with the fungus of the parent plant. 

 Bunyard, E. A., On Xenia. (p. 297—300.) 



Man\' experiments were made, but the only case in which any 

 direct influence was seen was when a flower of "Sandringham 

 Apple" was crossed with pollen of "Bismarck". 



Morris, Sir D. and F. A. Stockdale. The Improvement of 

 the Sugar-Cane by selection and hj'-bridisation. (p. 310 — 335.) 

 The attempt to grov; canes from seed for purposes of selection 

 has only recently been successful. In 1904 Lewton-Brain succeeded 

 in effecting artificial cross-fertilisation. Similar work has now been 



