10 - Mr. Roscoz on Artificial and Natural 
must also be observed that the primary distinctions of Linneus 
extend at once through the twenty-four classes, whilst those of 
Jussieu, arising from the cotyledons, extend only to three; the 
secondary, founded on the corolla, form only three more; and 
the subdivisions of these by the stamina and anthere, including 
the anomalous class of Diclines irregulares, form in the whole 
only fifteen classes, thus obtaining much less in point of distinc- 
tion by four separate dicke is than Linnzus has obtained 
by one. 
The consequence of this is, that there are on an average a 
much greater number of plants in each of the classes of Jussieu 
than in those of. Linnzus. In order to designate these classes, 
Annzus has recourse solely to the stamina, from the number, 
proportion, and situation of which he has formed all his distinc- 
tions, which he has comprised in one single expressive word, 
fully indicative of the grounds upon which the class is founded. 
J ussieu, on the contrary, in order to arrive at the distinctions of 
his classes, has taken a more circuitous path, and instead of 
referring to a single part, and defining it by a single word, has 
recourse to various peculiarities, as well in the mode of germina- 
tion as in the fructification. Thus the compound flowers, form- 
` ing a natural order, are designated by Linnzus by the term 
Syngenesia ; whilst Jussieu denominates them Plante dicotyledones, 
monopetale, corolla epigyna, anthere connate. ‘To say nothing of 
the. inconveniencies ee into the science by the substitu- 
essentiel dont Tournefort n'avoit pas connoissance, se trouve passer au | premier rang.” 
Extrait des Registres de la Soc. Roy. de Med. à Paris. 
But had Jussieu preserved a strictly natural method, he would have adopted the distinc- 
tions on the cotyledons, as suggested by Linnzus. In deserting these he has evidently 
fallen into an artificial one, having no connection whatever with the foundation on which 
his system is built. : 
tion 
