ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 615 



The details of the process are described in the case of a number of plants 

 belonging mostly to the Silencee and to the genera Saxifraga, Cucurhiia, Con- 

 volvulus, and Salix. 



Fertilization of Oxalis.* — Herr F. Hildebrand has made a series of 

 experiments on the fertility of the different forms of the various trimorphic 

 species of Oxalis. The following are among the more interesting results : — 



Of 0. Lasiandra the short-styled form is mostly known in cultivation. 

 It propagates itself by bulbs for many generations, and produces the short- 

 styled form only. It is incapable of self-fertilization, but abundance of 

 capsules are produced when brought into contact with the mid-styled form. 

 Of 0. tetraphylla, versicolor, hrasiliensis, and compressa, the long-styled forms 

 are entirely sterile with their own pollen. Of 0. lasiopefala the mid-styled 

 form is altogether infertile by itself, but produced abundance of seeds in 

 the neighbourhood of the mid-styled 0. articulata, which germinated into 

 hybrids. The mid-styled forms of 0. ohtusa and Vespertilionis, and the 

 short-styled 0. cernua and Deppii, were always sterile with their own forms, 

 and the same is the case with both short-styled and mid-styled 0. bifida, 

 though this species w^as fertile if the two forms were intercrossed, and with 

 the three forms of 0. hirta. 



In 0. Boiciei the short-styled form exhibits a very imperfect fertility 

 when pollinated from its own form, and the same is the case with the mid- 

 styled 0. catlierinensis. Seedlings from this form of this species produced 

 only mid-styled jjlants, while those resulting from the crossing of short-styled 

 and mid-styled forms gave birth to these forms only, and no long-styled. 

 Similar results were obtained with several other species. In 0. Valdiviana 

 and speciosa each of the three forms displayed a certain degree of fertility 

 when pollinated from its own form, which was stronger in 0. lohata, penta- 

 phylla, and crassipes; and in the cases of the'mid and long-styled 0. articulata, 

 the long-styled 0. incarnata, rosea, and Piottse, and the mid-styled 0. carnosa, 

 no self-sterility was exhibited. 



Fertilization of Scandinavian Alpine Plants.f — Herr C. A. M. Lind- 

 man has examined the very rich flora of the Dovrefjeld in reference to the 

 arrangements for fertilization. He finds a distinct tendency to a deeper 

 colour in the flowers than is displayed by the same species in the lowlands, 

 red and blue predominating. The great length of daylight appears to 

 increase the size both of leaves and of flowers, though in some species, on 

 the other hand, the flowers are diminutive in consequence of the low tem- 

 perature. Crowded masses of small flowers are very common. The number 

 of scented species is comparatively small, though the fragrance is sometimes 

 powerful. The scarcity of insects necessitates that there should almost 

 always be a provision for possible self-fertilization, and many species, else- 

 where heterogamous, are here homogamous. Notwithstanding the cold and 

 wet summer (1886), the plants observed almost invariably bore fruit. 



Chemistry of Germination.^ — M. A. Jorissen regards the greater part 

 of the nitrogenous substances formed in germination as derivatives of the 

 albuminoids. The result of germination is not always a reducing process. 

 The chief constituents of ash are phosphoric acid, potassa, magnesia, and 

 lime. During germination a transport is effected of these substances from 

 the cotyledons or endosperm to the embryo, this taking place at the expense 



* Bot. Ztg., xlv. (1887) pp. 1-6, 17-23, 33-40. 



t SB. Naturvetensk. Studentsallsk. Upsala, Nov, 11, 1886. See Bot. Centralb]., 

 XXX. (1887) pp. 125 and 156. 



% Jorissen, A., 'Les plie'nomenes chimiques de la germination,' 140 pp., Bruxellcs, 

 1886. See Bot. Centralbl., xxx. (1887) p. 5. 



