BOOKS AND CURRENT LITERATURE 103 



out recourse to the improbable hypothesis that we have terminal 

 microsporophylls. In fact, there is no evidence that the so-called 

 microsporophylls of WiUiamsonia gigas described on page 435 belonged 

 to that species. Fig. 549 no doubt represents a synangia-bearing 

 disk of a Williamsonia, but there is not the slightest evidence that it 

 belonged to Williamsonia gigas, or that it should be placed on the end 

 of a Williamsonia carpellary receptacle. Similarly the sterile disks or 

 infundibuliform organs have not been demonstrated to have been 

 borne on the apex of the receptacle. 



Professor Seward's position on the difficulty of founding well marked 

 botanical species upon material that is preserved as impressions is 

 well known and often sound. However, this does not justify the 

 assumption that all fossils that are superficially similar belonged to 

 the same species regardless of geographical position or geological 

 horizon. Such a method of treatment, well illustrated in Seward's 

 Jurassic flora, entirely obscures whatever real value such fossils may 

 have for purposes of deduction concerning geographical distribution, 

 the problems of paleogeography growing out of distribution, and the 

 bearing of fossil plants upon stratigraphy. 



On page 278 the genus Pelourdea is proposed for the long known 

 Yuccites vogesiacus of Schimper and Mougeot because the author con- 

 siders it undesirable to retain a designation suggesting false ideas with 

 regard to affinity. No one now supposes that this is suggested and such 

 a proposal is entirely unwarranted and can only be confusing instead of 

 clarifying. Moreover it is flying in the face of all canons of nomen- 

 clature. A name of a genus is simply a name, and ^e use generic 

 names for convenience chiefly, and not in a descriptive or phylogenetic 

 sense. I imagine that fully 25 per cent of the names in systematic 

 botany and zoology are equally inappropriate for one reason or another 

 but this does not afford any justification for attempting to replace 

 them. There is surely a difference between retaining a degree of per- 

 sonal independence in the face of codes and the persistent refusal to 

 recognize the fact that practices of this sort serve only to confuse the 

 subject. 



The proof-reading of the present volume is not as good as in the 

 preceding volumes, a number of the illustrations are unusually poor 

 and some might better have been omitted. Nor is the bibliography 

 reasonably complete. The latter like the text shows no method of 

 selection and appears to have just happened in the form in which it is 

 printed. — Edward W. Berry. 



