ZOOLOaY AND BOTANY, MICKOSCOPY, ETC. 677 



unilocular condition witli parietal placentation. But the most 

 remarkable changes are in the jilacenta, consisting in the outgrowth 

 from the ventral suture of two narrow parallel longitudinal plates of 

 a bright blue colour extending the whole length of the carpels. 

 In flowers in which this petalodic condition of the placenta is 

 present, there are no ovules in carj)els which are closed and unilo- 

 cular, while in cases where the ovary is still trilocular ovules in a 

 very rudimentary condition are present, reduced to a funicle and 

 irregular plate of cellular tissue more or less blue in colour, but 

 without any nucellus. This is the first instance recorded of petalody 

 or of any form of phyllody of ovules in Monocotyledons. 



Haberlandt's Physiological Anatomy of Plants.*— The special 

 characteristic of this work is that it V xugs prominently forward the 

 function of the various kinds of tissue, classifying them as forma- 

 tive, epidermal, mechanical, absorptive, assimilating, conducting, 

 accumulating, aerial, and secreting. It will illustrate the treatment 

 to mention that such terms as bast, cambium, &c., are not used by 

 the author as defining tissues found in special positions, but as tissues 

 performing special functions. 



Behrens's Text-book of General Botany.f — The speciality of this 

 text-book (translated from the German and revised by Prof. P. 

 Geddes) is the abundant detail in the account of the morphology of 

 the various organs of flowering plants. Under the head of Physio- 

 logical Botany large space is devoted to the phenomena of pollina- 

 tion and fertilization, and the illustrations are numerous and good. 



i8. PhysiologT.J 



Production of Male and Female Plants.§— Dr. H. Hoffmann has 

 attempted to determine the conditions under which male or female 

 individuals are produced in the case of the following dioecious 

 plants : — Lychnis diurna and vespertina, Valeriana dioica, Mercurialis 

 annua, Rumex Acetosella, Spinacia oleracea, and Cannabis saliva. He 

 finds that in most, if not all these cases, dense sowing increases the 

 proportion of male plants produced, and this results from an insuffi- 

 cient supply of nutriment. As a general law, the production of male 

 plants is promoted by the want of an adequate supply of food when 

 in an embryonal condition. 



Fertilization of Naias and Callitriche. || — According to Dr. B. 

 Jonsstm, the fertilization of the Naiadacca) is purely hydrophilous, 

 and takes place in the following way. The flowers are either monoe- 

 cious or dioecious ; in the monoecious species the male flowers are 



♦ Haberlanrlt, G., ' Physiologische Pflanzen-anatomie im Grundriss dar- 

 gesttllt,' 140 fij^'H. 8vo, Leipzig, 1884. 



t behreriH, W. J., 'Text-book of General Botany,' revised by P. Ged lea. 

 viii, and 'Al\ pp , 408 fig-i. 8vo, Edinbiirf^h, 188.'). 



J Tliia HubdiviHion nontainH (1) Kcprodii'-tion (including the formation of the 

 Embryo and accompanying procoHW'H); (2) (ierminution ; (H) Growth ; (4) Heapira- 

 tion ; (5) Movement; and (0) Chemical procenHOH (including Fermeutution). 



§ liot. Ztg., xliii. (1885) pp. H.'i-l.Oii, iCl-IJ. 



II LundH Univ. Ars-akr., xx. (1881; 20 pp. (1 pi.). 



Her. 2— V.;i,. V. 2 Y 



