DE CANDOLLE'S PHYTOGRAPHY. 285 



Some good advice follows about polemics and captious crit- 

 icism ; which we pass over, as seemingly superfluous, so long 

 as the botanists are almost without exception such peaceable 

 and good people. Something is said of the need of a right 

 appreciation of the extent of the science ; of the danger of 

 exclusive devotion to a single branch of botany, in which one 

 may lose all just perspective ; and, finally, of what accuracy 

 means in natural history as distinguished from mathematical 

 exactness. Everywhere the naturalist has to judge as well as 

 to measure. 



The third chapter discourses upon the manner of preparing 

 and editing botanical works, and the most advantageous modes 

 of publication, considers the different degrees of publicity: 

 for instance, complete and durable publicity is attained when 

 a Monograph of an order or genus, a Flora, a Species, or a 

 Genera Plantarum is published and placed on sale by the 

 booksellers ; or when an article or memoir is contributed to 

 any leading and well-known botanical journal, or to the bulle- 

 tin of a purely botanical society, which publishes with some 

 regularity and indexes its volumes ; or when printed in the 

 transactions or bulletins of any scientific society, if separate 

 copies in sufficient number are printed and fairly distributed 

 or placed on sale. The usage in some learned societies of 

 paging each memoir separately and placing it separately on 

 sale is referred to, with implied commendation. Let us add 

 that in all such separate issues, the original pagination of the 

 volume should be scrupulously preserved ; and it were better 

 that there should be no other. Less complete, but durable 

 publication is that of ouvrages de luxe^ so limited in number 

 of copies, and so high in price, that only a few libraries can 

 possess them; also articles in journals without full indexes, 

 or with indexes only to a series of volumes. 



Incomplete publicity is given when papers upon botany are 

 inserted in the voluminous transactions of general learned 

 societies, of which few individuals can possess the series or 

 find room for them ; also articles in reviews, encyclopaedias, 

 and the like, treating of many or of all sciences. Even jour- 

 nals of natural history alone fall under the ban, unless divided 



