ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 301 



orchards the wind plays but a very small part in the dissemination of 

 the pollen. The pollinating insects, however — bees, humble-bees, and 

 flies — as a rule visit a large number of flowers in succession on the 

 same tree, and, therefore, do not bring about true cross-pollination. In 

 the case of apples and pears, only a small proportion of the flowers 

 (5-6 p. c. and about 13 p. c. respectively) are habitually fertilised. 



Ornitliophilous Flowers.* — In addition to species already recorded, 

 Herr F. Johow describes three from the flora of Chile, viz. Phrygilanthus 

 tetrandrus and P. aphyllus, both parasitic plants belonging to the Loran- 

 thaceee, and Lobelia salicifolia. This last species is fertilised by hum- 

 ming-birds attracted by the minute insects which visit the flowers ; the 

 first by humming-birds in search of the small quantity of water at the 

 base of the perianth-tube. In both these cases self-polliuation is 

 rendered difficult by the structure of the flower. 



Gynodioecism of Myosotis palustris.f — According to K. Fritsch, the 

 small-flowered variety of this plant, which has been described under 

 several names, is in reality a female form. It is distinguished not only 

 by its smaller flowers, but also by the absence of pollen in the anthers, 

 which do not assume the oblique position which they occupy in the 

 perfect flowers, but are always in close contact with the corolLi tube. It 

 frequently differs also in its hairiness. A corresponding structure has 

 not been observed in other species of Nyosotis, but a similar gynodioecism 

 occurs in Anchusa officinalis and Echium vulgare. 



Proterogyny of Lychnis flos-cuculi.J — A. J. M. Garjeanne records 

 the interesting fact that in a number of plants of this species, which 

 blossomed for a second time in the autumn, a large number of the flowers 

 were homogamous, while two were distinetly proterogynous, in contrast to 

 the normal proterandrous arrangement. In these flowers the stigma was 

 in a receptive condition, and the pollen-grains were fully developed. 



Impregnation in Angiosperms.§ — We have from Miss Ethel Sargant 

 a valuable epitome of the important results of recent investigations on 

 this subject, especially in reference to the occurrence of double impreg- 

 nation, which has now been established in twenty species, representing 

 five natural orders, Liliaceae, Orchidese, Kanunculaceas, Compositse, and 

 Monotropeae ; the movement of the generative nucleus ; the homology of 

 the embryo-sac and its contents ; and the nature of the triple nuclear 

 fusion. The bibliography enumerates forty-five different papers on. 

 these subjects. 



(2) iNutrition and Growth (including Germination, 

 and Movements^of Fluids). 



Influence of Pressure on Chlorophyll: Assimilation. || — J. Friedel 

 states more accurately, in the following words, the law at which ho has 

 arrived respecting the variations in chlorophyll assimilation caused by 

 changes in the pressure of the atmosphere. Decrease alone of the total 



* Verhandl. deutsch. wissenBch. Ver. Santiago, v. pp. 1-22 (2 pis.)- See Bot. 

 Centralbl., lxxxv. (1901) p. 210. Cf. this Journal, ante, p. 58. 

 t Ber. Deutsch. Bot. Ges., xviii. (1901) pp. 472-80. 

 X Beih. z. Bot. Centralbl., x. (1901 ) p. 51. 

 § Ann. of Bot., xiv. (1900) pp. 689-712. 

 || Comptes Kendus, exxxii. (1901) pp. 353-5. Cf. this Journal, 1900, p. 693. 



