g8 BOTANICAL GAZETTE. 



the embryo-sac is not spoken of, although repeated observations have 

 proved that there is at first a distinct separation between the sexual 

 cell and the enlarging embryo sac. The "primordial mother-cell of 

 the embryo-sac" can be clearly made out also by any ordinarily care- 

 ful observer, and then its breaking up into the axial row of four or five 

 cells, the uppermost one of which contains the vesicle and "syner- 

 gides," the second becomes the embryo sac and the two or three re- 

 maining ones subsequently secrete endosperm, can be readily traced. 

 This is mentioned simply because it seems a pity that such an inter- 

 esting line of investigation was not suggested. There is. an abundance 

 of work suggested, however, for the most active class, and we hope 

 that very many classes will undertake it. The author plunges "in 

 medias res," or begins at the beginning, whichever way one Iooks at 

 it, by introducing as the subject of the very first paragraph, "Proto- 

 plasm " This plan he follows throughout, not avoiding the difficult 

 points, but by directly encountering them, before the student knows it 

 he has a clear idea ot some very uncertain subjects. With Dr Gray's 

 admirable new text book on Structural Botany and this upon Physiol- 

 ogy, the student of botany can get a very excellent knowledge of the 

 science. The arrangement of the book is mostly new and at first 

 glance most excellent, a thing of comse to be tested in the class room. 

 As to innovations, the author himself calls attention to two. In Chap- 

 ter VI he recognizes seven well marked kinds of tissue, viz.: Parenchy- 

 ma, Collenchyraa, Sclerenchyma, Fibrous Tissue, Laticilerous Tissue, 

 Sieve Tissue, and Tracheary Tissue. Of course these include a great 

 many varieties which pa?.s into each other by almost insensible grada- 

 tions. The other innovation "consists in raising the Protophyta, Zy- 

 gosporese, Oosporeie, and Carposporeie to the dignity of Primary Di- 

 visions of the vegetable kingdom, co ordinate with the Eryophyta, 

 Pteridophyta and Phanerogamia. " The book also contains constant 

 suggestions with regard to laboratory work, such as the best plants 

 from which to get certain tissues, etc., and the best method of treat- 

 ment. This enables the student to go into the laboratory alone, or 

 rather with the aid of the experience of Prof. Bessey, one of the mostsuc- 

 cessfuU of teachers, and perform satisfactorily ah the elementary 

 work in the histological structure of plants. We would most 

 cordially commend the work to the use of all professors and students 

 of botany as not only the best American book upon the subject, but 

 the only one. — J.M.C. 



The Valley N.aturalist, Vol. II. No. i — This enterprising 

 journal has aga'n made its appearance and this time it appears that ils 

 subscription list makes its success assured. It has now i6 pages and 

 a cover, the subscription price being I1.50. There is surely room for 

 such a publication in the great Mississippi Valley, but a constituency 

 of scientific subscribers and contributors is exceedingly slow to build 

 up. The publisher is Mr. Henry Skaer, N.W. Cor. Third & Pine 

 Sts., St. Louis, Mo. 



