328 EXPEKIMENT STATION RECORD. [Vol.43 



Studies on pollen, F. i\I. Andrkws {Proc. Iml. Acad. Sci., 1917, p. 16.]). — 

 Tlie author reports the general results of investigations as carried out on the 

 beliavior of pollen in 43.") plants with respect to a culture medium of cane sugar. 

 Of these, 110 showed no response as regards growth (although a wide range of 

 percentages was employed), and the remainder showed a more or less pro- 

 nounced growth. 



Pollen development in Cinnamoniuni and the phylogenetic significance 

 of pollen types, G. Tackholm and E. Soderberg (Arkiv. Bot., 15 {1917), Xo. 

 8, pp. 1-1 Jf, fiff. 1). — This is a study by the authors of Cinnamomum sieboldi, 

 which offers a new example of a dicotyledonous plant in which (as in most 

 monocotyledons) the pollen grains develop by successive cell divisions, witli a 

 consideration of the pliylogenetic significance of the facts observed. 



The origination of variations in Anemone hepatica, S. Galant {Biol. 

 ZenthL, 39 {1919), No. 12, pp. 529-535, figs. 2).— This contains statistical notes 

 regarding certain flower variations in A. hepatica. 



The genetics of flower coloration in Tropasolum niajus, H. Rasmuson 

 {Bot. Notlser, No. 5 {1918), pp. 253-260).— It is stated that the genotypic dif- 

 ference between plants of T. majus with dark yellow and such plants with 

 light yellow flower color is due to a single factor, dark yellow being dominant. 

 The difference between red and yellow flowered plants may be conditioned by 

 a single factor. 



Anatomical structure of wheat heads as related to their position on the 

 stem and to the influence of external conditions, W. Heuseu {Kiilin Arch., 

 6 {1916), pt. 2, pp. 391-1(36, figs. 11). — In summer wheat, the heads show mor- 

 phological and anatomical characters corresponding to stem position as de- 

 scribed. They also show modifications corresponding to soil moisture and nu- 

 triment. 



The fruit of Opuntia fulgida: A study of perennation and proliferation 

 in tlie fruits of certain Cactaceae, D. S. Johnson {Carnegie Inst. Wash. Pub. 

 269 {1918), pp. 62, pis. 13). — This paper embodies a discussion of the occurrence 

 and significance of a number of striking peculiarities in the development and 

 fate of the persistent, self-propagating fruits of certain Opuntias. It is con- 

 cerned primarily with the perennation and vegetative propagation of the ovary 

 of O. fulgida, chosen for special consideration because of its remarkable power 

 of budding off secondary flowers from the primary ones and also of forming 

 new flowers and vegetative shoots from the long-persistent fruits. 



The fact that O. fulgida and other species have series of fruits showing 

 various degrees of sterility, from those with scores of seeds to those that are 

 entirely seedless, is not considered conclusive evidence that seed production 

 is really on the way to complete extinction in these plants. Nor is tlae corollary 

 that propagation by seeds is being replaced by the proliferation to new plants 

 of fallen fruits regarded as very significant. On the contrary, the stem-like 

 character of the fruits in this genus results in the persistence of many sterile 

 ovaries, such as would, in many less fleshly angiosperms, wither and fall off 

 soon after blooming, instead of maturing into seedless fruits as here noted. 



Revision of Ichthyomethia,. a genus of plants used for iioisoning fish, 

 S. F. Blake {.Tour. Wash. Acad. Sci., 9 {1919), No. 9, pp. 241-2.52).— The g^nus 

 Ichthyomethia, here reviewed, is said to be of economic importance as furnish- 

 ing a medicine, a fish poison, and a valuable timber. 



The Uredinales of Delaware, H. S. .Tackson {Proc. Ind. Acad. Sci., 1917. pp. 

 311-385). — This account of Delaware Uredinales is the result of a study of the 

 rust flora of that State begun in 1906. The list contains 129 species, whicl 

 are recorded on 232 different hosts. 



