2:37 



true that the very general neglect of paleobotany by botanists is 

 most unfortunate. Lack of perspective always means distortion, 

 and perspective in evolutionary botany is practically impossible 

 without regarding the evidence offered only by fossil plants. 

 The customary omission of any reference to this record in school 

 text-books is responsible for the very common impression of 

 students who have had only elementary courses that mosses 

 are descended from liverworts, ferns from mosses, and gymno- 

 sperms from ferns. Many will realize for the first time, on read- 

 ing this book, that the derivation of the leafy sporophyte from 

 the sporogonium of the bryophytes is clearly not the only possible 

 view, but that "the theory that the asexual plant of the higher 

 Cryptogams was derived from a sporogonium is unsupported by 

 [fossil] evidence." "The idea of the superior primitiveness and 

 antiquity of plants of the Bryophyte type remains a pure as- 

 sumption and receives no support from our knowledge of ancient 

 vegetation" (p. 224). "On this theory, then, the sexual pro- 

 thallus and the asexual plant are both alike derived from a thallus, 

 and may once have been perfectly similar to each other; the one 

 has gone up and the other down" (p. 226). The reviewer calls 

 to mind more than one college text that contains not even a hint 

 of this fossil evidence and the conclusion to which it leads. 



Omissions of like kind, however, are chargeable to the book 

 under review. In Chapter I, discussing the Darwinian theory, 

 the mutation theory is absolutely ignored, and one reads (p. 13) 

 with nothing short of amazement, that, "Natural Selection 

 appears to be the only theory at present in the field, which can be 

 said to give at all a satisfactory explanation, by means of natural 

 causes, of the origin of adaptations." Of similar nature is the 

 regarding of Isoetes as, without question, belonging to the Selag- 

 inellaceae. Again, in discussing the relation between the colors 

 of flowers and insect visitation (pp. 41, 96-97), the recent work 

 of Plateau and others receives no mention. Of course, in a 

 popular book of restricted compass, one cannot go into a dis- 

 cussion of all the controverted questions of the specialist, but on 

 the other hand, it hardly seems fair to the popular reader, to 

 leave him, in such cases, with the impression that only the ex- 

 planation or view given is held or tenable. 



