224 EXPERIMENT STATION EECORD. 



Origin of species by mutation, A. W. Sutton (IV. Conf. Internat. Oen^iique 

 Paris, Compt. Rend, et Raps., 1911, pp. 158, 159; a'bs. in Bot. GentU., 123 (1913). 

 No. 10, p. 2Jf1). — The author states that observations extending over 40 years 

 have convinced him that, while permanent variations may appear and retain 

 their distinctive characteristics wjien isolated and grown (some being, however, 

 only fluctuating variations tending soon to lose their identity), there is nothing 

 approaching a really new species which has arisen by so-called mutation in 

 the plants observed. 



On the principle of the coalescence of living plasmas and the origin of 

 races and species, A. Gautiee {IV. Conf. Internat. Gen6tique Paris, Gompt. 

 Rend, et Raps., 1911, pp. 79-90, fig. 1; abs. in Bot. GentU., 123 (1913), No. 9, pp. 

 214, 215.) — The author sums up the results of studies extending over some 

 years. 



Observations on cross-fertilization, grafting, etc., are claimed to show that 

 somatic plasma possesses a property similar to that of the germ plasm, namely 

 the power to transmit to the bud and to the ovary of the plant a modification 

 which is immediately apparent and which in some cases may be transmitted 

 to the offspring. The step from one race or species to another corresponds to a 

 modification of the chemical principles essential to the race or species, this 

 chemical differentiation being the sign of a corresponding variation in the 

 protoplasm, resulting in a sudden alteration of function, of product, and of 

 growth as regards external form. The coalescence of vegetable or somatic 

 plasma may be as effective as that of germ plasm in the production of new 

 races, uniting species and even genera. The stimulus may originate from 

 insects, microbes, etc., acting directly or indirectly toward these results. 



The author concludes that it is by the union or symbiosis of plasmas, sexual 

 or somatic, resulting from fertilization, grafting, or parasitic or traumatic 

 action, that, either modifying the relation of certain ferments or preventing 

 their formation, gives rise to those abrupt changes by which new races or 

 species are produced; and that the variations of the individuals and of the 

 races thus formed do not transgress the limits beyond which analogy with 

 anatomical structures or with specific chemical principles no longer exists. 



Studies of natural and artifi.cial parthenogenesis in the genus Nicotiana, 

 R. Weixington {Amer. Nat., J^l {1913), No. 557, pp. 279-306; ahs. in Internat. 

 Inst. Agr. [Rome'], Mo. Bui. Agr. Intel, and Plant Diseases, 4 {1913), No. 7, p. 

 1039). — The author reports several hundred attempts with stimuli caused by 

 foreign pollen, mutilations, fumigation, and infections on numerous species and 

 varieties of Nicotiana to produce parthenogenesis in the seed without success, 

 and concludes that it probably does not occur in the forms tested. 



An extensive bibliography is given. 



Periodicity of specific characters, P. Vuillemin {Bui. Soc. Set. Nancy, 3. 

 ser., 13 {1913), No. 3, pp. 179-218, figs. 13).— The author concludes an account 

 of studies made by him on morphology in different stages, as noted in a number 

 of plants, by stating that various forms of polymorphic plants or organs thereof 

 may appear in a determinate order, which fact requires in such cases that these 

 successive characters be employed to give a complete definition of the species. 

 It is admitted that this habitual periodicity may be interfered with by external 

 agencies, but it is still held that those teratological characters which exhibit 

 periodic polymorphism are to be regarded as specific. 



Biology and radio-activity, G. Petit {Rec. MM. V6t., 90 {1913), No. 17, pp. 

 584-590, figs. 2). — Besides brief mention of some work by other investigators, 

 an account is given of recent studies by the author regarding the influence of 

 radio-activity on rye grass, wheat, and corn. Some experiments on the last 

 named showed a striking acceleration of growth, the results in general con- 



