Botany 



No. 4. CONARD, H. S. The Waterlilies. A Monograph of the Genus Nymphata. 

 Quarto, xni+279 pages, 30 plates, including 12 plates colored to life, 

 82 text figures. Published 1905. Price, $6.50. 



The paper embodies the results of an attempt to bring together the knowledge 

 of this group in all of its botanical relations, inclusive of the results of hybridiza- 

 tions, and some of the details of culture and uses. The general life-history and 

 physiology of the group, as well as the distribution of the separate series in 

 geologic and present time, receive full consideration. The taxonomic conclusions 

 are based upon the fullest anatomical detail, and the principal forms are well illus- 

 trated. An extensive bibliography is appended. 



No. 94. CONARD, HENRY S. The Structure and Life-History of the Hay-scented 



Fern. Octavo, 56 pages, 25 plates Published 1908. Price $0.50. 

 Presents a detailed description of the life-history of Dennstcedtia punctilobula, 

 with results of cultures and detailed anatomical studies. 



No. 37. HARPER, R. A. Sexual Reproduction and the Organisation of the Nucleus 

 in certain Mildews. Octavo, 104 pages, 7 plates. Published 1905. 

 Price $0.75. 



A presentation of the results of the author's researches upon the organization of 

 the resting nucleus and its relation to the processes of nuclear fusion and division in 

 the mildews. Evidence bearing upon the individuality of chromosomes is pre- 

 sented, alternation of generations in the Ascomycetes is predicted and it is con- 

 cluded that the ascocarp originates in a sexual apparatus. The desirability of 

 basing phylogenetic conclusions primarily upon morphological data is made evident. 



No. 30. SHULL, G. H. Stages in the Development of Sium cicuta folium. (Paper 

 No. 3, Station for Experimental Evolution.) Octavo, 28 pages, 7 

 plates, 11 text figures. Published 1905. Price $0.25. 

 For description see page 97. 



No. 112. SHULL, G. H. Bursa bursa-pastoris and Bursa heegeri: Biotypes and 

 Hybrids. (Paper No. 12, Station for Experimental Evolution.) Oc- 

 tavo, 57 pages, 4 plates, 23 text figures. Published 1909. Price $0.50. 

 For description see page 99. 



No. 82. LLOYD, FRANCIS E. The Physiology of Stomata. Octavo, 142 pages, 40 

 text figures, 14 plates. Published 1908. Price $1.50. 



The investigation described in this paper concerns the questions as to the part 

 played by stomata in the regulation of transpiration and the cause of stomata move- 

 ment. The physiological rather than the physical view of transpiration is favored 

 by the results. Some new facts concerning guard-cells tend to show that these or- 

 gans are secretory rather than photosynthetic. Methods of fixing stomatal struc- 

 tures for examination and a great mass of data bearing on the daily periodicity of 

 transpiration are given. An important contribution on a much-vexed question. 



No. 139. LLOYD, FRANCIS E. Guayule: A Rubber Plant of the Chihuahuan Desert. 

 Octavo, vin+213 pp., 46 pis., 20 figs. Published 1911. Price $3.50. 



This publication embodies the results of an organized attempt to bring under cul- 

 tivation a hitherto feral desert plant, together with an extensive ecological study of 

 the same under normal and cultural conditions. Careful consideration is given to the 

 questions of rate of growth and reproduction of the guayule in its native habitat, 

 and a large body of pertinent data is given. The various conditions of climate, soil, 

 vegetational environment, and parasitism affecting the plant are presented in this 

 connection. The life history, habit, anatomical and histological structure of the 

 wild and cultivated forms are minutely described and compared, with the purpose of 

 developing exact knowledge concerning the relation between growth and the rate of 

 rubber secretion. 



