634 EXPERIMENT STATION RECORD. 



many others, and the information is brought together in what is called a handbook 

 for the recognition of the injury and estimation of damage done ])y smoke, gases, 

 and similar agents. A^ter a general discussion of the various sources and kinds of 

 injurious smoke and gases, the authors consider a numberof them in detail, chapters 

 being devoted to the injury caused by sulphurous and sulphuric acids, chlorin and 

 hydrochloric acid, hydrofluoric, nitric, and acetic acids, ammonia, bromin, coal tar 

 and its products, asphalt, illuminating gas, etc. Means for preventing some of the 

 injuries are discussed, and an extended bibliography of references to the literature 

 of the subject completes the work. 



Injurious efifects of premature pollination, C. P. Hartley ( f ^. aS'. Dcpt. Agr., 

 Bureau of Plant Indvi<tnj Bui. 2-2, pp. 48, ph. 4, .fig- !)■ — The investigation here 

 reported seems to indicate that decidedly injurious effects may be obtained by pre- . 

 mature pollination, showing the necessity of careful consideration as to the time for 

 applying pollen to the stigmas in experiments in plant breeding. The author con- 

 ducted experiments with tobacco, cotton, orange, and tomato flowers, contrasting 

 the effects of immature and mature pollinations. It was found that flowers which 

 mature their pistils before their stamens were uninjured by premature pollination, 

 while those that mature their anthers and stigmas at the same time were injured. 

 The application of good tobacco pollen to immature tobacco pistils caused the flow- 

 ers so treated to fall from the plant because of the growth of the pollen tubes into 

 their ovaries. Somewhat similar results were obtained with tomatoes, only 2 out of 

 40 blossoms setting fruit when prematurely pollinated. Tol)acco and tomato jilants 

 were found to sometimes set and ripen fruits without the flowers having received 

 any pollen, but such occurrences w^ere rare and the fruits contained no fertile seeds. 

 The experiments described show that while some flowers can be successfully polli- 

 nated at the time emasculation of the flower is performed, others can not, and no 

 arl)itrary rules of procedure can be given for all flowers. 



Mendel's principles of heredity. A defense, W. B.\teson \('amhrklge Vniv. 

 Pre.%% 1902, pp. 212). — The author ])resents a translation of (Tregor Mendel's experi- 

 ments in plant hybridization ( E. S. R. , lo, p. 744) an<l answers l)y argument Wel- 

 don's criticisms (E. S. R., 14, p. 44(>) of Mendel's work. The problems of heredity 

 are stated and their solution discussed. A bibliography of .".() papers on liybridiza- 

 tion is aj)pended. 



Experimental studies in the physiology of heredity, W. Bateson and Miss 

 E. R. Saunders {Bpta. to Emlution Com., Roy. Hoc. \^Lon,don'\, 1902, pp. 160; abs. in 

 Bot. Centhl., 90 {1902), No. 37, p. 291). — The results of extensive breeding experi- 

 ments with poultry and plants are given. So far as the results of the experiments 

 with plants are concerned, the phenomena ol)served in Lychnis, Atropa, and Datura 

 follow Mendel's law with considerable accuracy, and no exceptions were discovered 

 that did not appear to be merely fortuitous. In the case of the experiments with 

 Matthiola the phenomena were much more complex. In some cases the restdts fol- 

 lowed Mendelian principles, while in others they seemed to depart, but could be 

 grouped into fairh' definite classes, but their nature was obscure. The paper con- 

 cludes with a general discussion of heredity as exemplified by Mendel's law. 



Variation in Trillium grandiflorum, H. W. Britcher [Maine Sta. Bui. 86, pp. 

 169-196, ph. 5). — A record is given of the variations observed ni 185 specimens of 

 Trillium graudijloruui. 



Comparative anatomy of the styles and stigmas of phanerogams, E. (iuE- 

 GUEN {Jour. Bot. [Paris], 16 {1902), iS'o.s. 1, pp. 15-30; 2, pp. 48-65; 4, pp. 138-144; 

 5, pp. 167-180; 8, pp. 280-286; 9, pp. 300-313, ph. ^1").— Results of an extensive 

 study of the anatomical structure of the styles and stigmas of the jihanerogams are 

 given, the notes being arranged according to plant families. As a rule the complex- 

 ity of the tissues of the styles increases with the greater specialization of the plant. 

 The stigmas and stigmatic surfaces are le.ss constant in their structure, being modi- 



