1886.] BOTANICAL GAZETTE. at 
Bernard de Jussieu, while arranging the great Jardin des Plantes 
at Paris, pondered deeply the problem of a natural system. Bot- 
anists of lesser note were all occupied with the same question. 
While at the university in Upsala, in 1829, Linneus was 
prompted by reading a discourse by Vaillant, on the structure of 
flowers, to examine very closely the stamens and pistils of plants. 
These appendages he discovered to be essential to the vegetable 
and to assume as much variety as the petals; hence he conceived 
that they might be made the basis of a new system of classifica- 
tion. He thus early laid the foundation of that sexual system 
which he afterwards wrought up to such perfection. According 
to this system were arranged all his succeeding botanical obser- 
vations. : 
The Linnean or sexual system is briefly as follows: All known 
plants are divided into 24 classes, the characters of which are 
established upon the number or upon the difference of situation 
or arrangement of the stamens; the orders as far as possible on 
a similar number, situation or arrangement of the pistils. For 
example the classes are Monandria, Diandria, Triandria, ete. ; 
stamens and pistils are present in all of the classes,to the 23d. 
The 24th class is the Cryptogamia containing even to this day 
many plants the mode and organs of whose fructification are not 
yet ascertained. Linnzeus did not publish his system till he went 
to Holland, in 1735. Having paid a visit to Dr. Gronovius, of 
Leyden, the latter returned it and saw his Systema Nature in 
manuscript, which astonished him, and he requested Linnzus” 
permission to get it printed at his own expense. The Dutch 
botanists received Linneus with the utmost cordiality and all 
immediately embraced and adopted his system. He rearranged 
one day overthrow his own system. He gruffly called in question 
the genus Dillenia, named by Linnus in his honor, but whic 
