284 Scientific Intelligence. 



foliata; Ruiz and Pavon figured them in (7. hlfiora; Dr. Torrey noticed 

 them independently in his Flora of the Northtrn States more than thirty 

 years ago, and in 1830 described their true structure, (see also his Flora 

 of Neio York, 1, p. 428). Since then, although overlooked by DeCan- 

 dolle, they have been observed and investigated by Brongniart {Jtmieu, 

 Mem. Malpigh. in Archives da Museum^ 3, p. 84), &c. — The vexed ques- 

 tion of the principles of limitation of genera being raised, is discussed 

 from a practical point of view by Dr. Hooker and Mr. Bentham ; and an 

 interesting note on the principles of generic nomenclature is drawn up by 

 Mr. Bentham, in a separate article, which, being brief and important, we 



cite entire : 



Memorandum on the Principles of Generic N'omenclature ^ as referred 



to in the preceding paper ; draivn up by G. Bentiiam, Esq., F.L.S. 

 "Two of the chief objects of the systematist in botany are, first, to col- 

 lect plants into natural groups of successively higher value and greater 

 scope according to their mutual affinities; and, secondly, to fix upon cer- 

 tain stages of these successive groups to which names should be attached 

 for the purpose of reference. It is to the latter of these objects that we 

 would now chiefly direct our attention, 



"The grand object accomplished by Linn^us in his nomenclature was 

 to create a language by which plants could be spoken of, and by means of 

 which groups of species (called genera) could be refen'ed to, classed, and 

 treated of as easily as the species themselves, 



"He accordingly, treating his genera as entities (to use a word of 

 Jeremy Bentham's) as natural as species, distributed them for practical 

 purposes into his well-known artificial Chisses and Orders. 



" The evident facilities for scientific study afforded by this grouping of 

 species into natural genera, prompted Jnssieu to carry the principle much 

 higher; and, whilst he retained the Linnean genera as the basis of botan- 

 ical language, he established, fur the purposes of science, his ^natural 

 07*ders or groups of genera, which are in fact nothing more than genera 

 of a higher grade; and he distributed these orders or large genera into 

 classes and subclasses. This system of — 



Species grouped into natural genera, 

 Genera grouped into natural orders, and 

 Orders arranged in classes more or less natural ; 

 with a language of 



Substantive names for the genera, 

 Adjective adjuncts for the species, and 

 Substantively taken adjectives for the orders, 

 has been ever since universally followed in theory, but has been most in- 

 conveniently departed from in practice, 



^ "With the great increase in the number of species known, and the 

 increased facilities for the study of affinities aflx)rded by the Linnean lan- 

 guage and the Jussieuan principles, botanists became aware that the 

 species of a genus and the genera of an order could be collected into 

 intermediate groups, as natural and as well defined as the genera and 

 orders themselves ; and that nances were, for scientific purposes, as useful 

 for these subordinate groups as for those genera or orders. 



"To^ carry this into practice two ditferent courses have been adopted : 

 " 1. To maintain the original genera and orders in their integrity (^^^^P* 

 where a mistaken view of their affinities required them to be remodelled), 



