ZOOLOGY AND BOTANY, MICROSCOPY', ETC, 249 



y3. Physiology." 

 CD Reproduction and G-ermination. 



Distribution of the Sexual Organs in the Vine-t — Prof. E. Eatbay 

 records a number of observations which support his statement that there 

 is a certain amount of ditferentiation of the sexes in the cultivated vine. 

 Many of the flowers are functionally female ; they contain stamens, but 

 the pollen-grains have no power of putting out pollen-tubes ; and these 

 female flowers differ somewhat in form and appearance from the her- 

 maphrodite flowers. He finds, moreover, that those individuals which 

 bear female never bear hermaphrodite or male flowers. The male 

 individuals also never bear female, but not unfreqnently hermaphrodite 

 flowers. The hermaphrodite individuals may bear male but never 

 female flowers. Dr. Rathay suggests that the wild ancestor of the 

 cultivated grape-vine must have been dioecious. 



Constancy of Insects in visiting Flower s4 — Observations made hy 

 Dr. M. Kronfeld on Apis melliftca and Bomhus Jiortorum tend to show 

 that these insects will, on the same flight, confine their visits to the 

 same species of flower, even when a number of others are equally acces- 

 sible which would just as well afford them a supply of nectar and pollen. 



Fertilization of Lonicera japonica.§ — Mr. T. Meehan describes, in 

 relation to their mode of fertilization, three ditierent forms of this 

 species grown in American gardens. He states that, notwithstanding 

 the length of the corolla-tube, it is, after the dehiscence of Ihe anthers, 

 so completely tilled with nectar that bees and other short-tougued. 

 insects have no difficulty whatever in obtaining it. These visit the 

 honeysuckle in large numbers, and, from the position of the stamens 

 and stigmas, can in no possible way aid in fertilization. Mr. Meehan 

 sees in this evidence of design for the benefit of the insect rather than of 

 natural selection for the benefit of the flower alone. 



Fertilization in the Nyctagines. 1| — Dr. A. Heimerl describes tlie 

 mode of pollination in several species belonging to this order. In 

 Oxyhaphus viscosus, the styles and filaments undergo several changes in 

 direction, from nearly straight to strongly curved, ultimately bringing 

 the stigma and anthers in close proximity to one another. The showy 

 scented perianth appears to point to the visits of insects, and cross- 

 pollination is not excluded ; but, on the other hand, the structure seems 

 contrived to ensure the possibility of self-pollination. The main facts 

 are the same in Mirahilis Jalappa, and in the night-flowering M. longi- 

 flora. In other genera of the order, Boerhavia, Acleisantlies, PentacojpJirys, 

 and Selhiocarpus, there is a gradual transition from the ordinary open to 

 cleistogamous flowers which are, of course, exclusively self-fertilized. 

 In the suborder Pisoniefe, on the other hand, consisting of tropical and 

 subtropical trees and shrubs, cross-pollination is insured by diclinism, 

 or the suppression of the pistil and the stamens respectively in the male 

 and female flowers. 



* This subdivision contains (1) Eepioduction and Germination; (2) Nutrition 

 and Growth (including Movements of Fluids) ; (3) Irritability ; and G) Chemical 

 Changes (including Eespiration and Fermentation). 



t SB. K.K. Zool.-Bot. Gesell., xxxviii. (1888) pp. 87-92. 



X Abh. K.K. Zool.-Bot. GeselL, xxxviii. (1888) pp. 785-6. 



§ Froc. Acad. Nat. Sci. Philad., 1888, pp. 279-83. 



11 Abh. K.K. Zool.-Bot. Gesell., xxxviii. (1888) pp. 7G9-74. 

 1889. S 



