November 5, 19 lo] 



SCIENCE 



649 



CEnothera taxonomy and how circumscribed 

 is our present horizon. Every years adds some 

 new species which have been tested in the ex- 

 perimental garden, the only safe way of deter- 

 mining for most of the a'notheras their true 

 characters and justifying the publication of 

 species. With these conditions in the group 

 some years must elapse before we shall be in a 

 position to take a general survey of the field. 



A chapter on " The Cultural History of 

 CEnothera " presents an interesting account of 

 the pre-Linna3an references to o?notheras with 

 a number of figures reproduced from old works. 

 This account leads up to a discussion of the 

 origin and status of CEnothera Lamarchiana, 

 a matter of fundamental significance in any 

 consideration of the value of this plant as 

 representative of a mutating species. Gates 

 accepts without qualifications the opinion of 

 De Vries that Lamarchiana was collected in 

 America by Andre Michaux about the end of 

 the eighteenth century. The evidence for this 

 view rests on a specimen in the Museum 

 d'Histoire Naturelle at Paris. The photo- 

 graph of this plant published by De Vries and 

 only figured in part by Gates shows a plant 

 with narrow-lanceolate leaves strongly petioled, 

 narrow bracts, and very long sepal tips. That 

 this plant could have been related to Lamarch- 

 iana with its ovate-lanceolate leaves almost 

 sessile, broader bracts, and shorter sepal tips 

 seems to me scarcely possible, and I venture to 

 believe that neither Bartlett nor ShuU, both 

 CEnothera specialists, will follow De Vries in 

 this identification. 



Accepting this identification of De Vries, 

 Gates finds no diificulty in believing that 

 Lamarchiana, as a native American species, 

 established itseK on the Lancashire coast of 

 England previous to 1800, and that the figure 

 of Sowerby, 1806, is of this plant in spite of 

 the fact that the flowers as drawn are not so 

 large as those of Lamarchiana, the position of 

 the stigma not so high, and that no mention is 

 made in the description of the very conspicu- 

 ous red papillae upon the stem. An alternative 

 possibility that the plant of Sowerby was a form 

 related to biennis finds no favor with Gates. 

 The chapter concludes with accounts of a 



number of races of Lamarchiana now in culti- 

 vation or otherwise recognized. Gates accepts 

 with De Vries the suggestion that the source 

 of the Lamarchiana introduced into cultivation 

 by Carter and Company about 1860 may have 

 been not Texas, as they state, but England. 



Chapters IV. and V. give descriptions of the 

 " mutation phenomena " in Lamarchiana and 

 other species and include observations of his 

 own as well as those of De Vries and other 

 authors. There is also described in these 

 chapters the results of many breeding experi- 

 ments involving the " mutants " as parents. 

 These chapters should be read with the follow- 

 ing points in mind as reservations of prime im- 

 portance for judgment on the deductions. 

 Recent work has shown that the germination 

 of very many seeds of Oenotheras is usually 

 delayed far beyond the time generally allowed 

 by the preservation of seed pans. Although 

 the facts of delayed germination and seed 

 sterility have been recognized, few investigators 

 have taken the trouble to make counts of the 

 seeds sown and until recently none have ob- 

 tained complete germination as established by 

 experimental methods properly checked through 

 the examination of the residue of sterile seed- 

 like structures. Consequently we can not feel 

 confident that the records of any cultures of 

 CEnothera so far reported are complete for 

 their possible progeny. The percentages cal- 

 culated for " mutants " and the ratios of classes 

 in breeding experiments can not be accepted 

 as final in exact genetical work. We are not 

 in a position even to guess what may be the 

 changes of front when exact data become 

 available. 



In Chapter VI., on the " Cytological Basis of 

 the Mutation Phenomena," will be found an 

 account of Gates's own contributions in cytology 

 which have been noteworthy. A good descrip- 

 tion of the reduction divisions in the pollen 

 mother-cells paves the way for the discussion of 

 irregularities in the distribution of chromo- 

 somes whereby gametic nuclei may be formed 

 with more or with fewer chromosomes than 1, 

 the normal number. From such gametes, fer- 

 tile zygotes are occasionally formed that give 

 rise to Oenotheras with high counts of chromo- 



