150 FIRST JOURNEY IN EUROPE. [1839, 
Britain. He cares little, however, for proper system- 
atic botany, for which I am sorry. He has shown me 
some curious things. 
I have learned from Brown the character he ob- 
served in our species of Rhexia, that is, the true genus 
Rhexia: the unilocularity of the anthers. .. . 
Tuesday evening, March 12.— After a_ hard 
day’s work I finished on Monday evening with the 
Linnean herbarium, which [ found more interesting 
than I expected and more satisfactory, as it is in 
really good state, carefully taken care of, ete. I had 
some very good notes to make. I assure you I feel 
much gratified to have studied this collection, which, 
with the Gronovian, enables us to start fair as to Lin- 
nan species. Do you know that Acer saccharinum, 
Linn., is A. eriocarpum (spee. Kalm)! Look at Lin- 
neus “ Species Plantarum ” (which you have not, un- 
fortunately, though it is the most necessary of books ; 
you will receive it at the same time as this letter or 
nearly) and you will find that the description is all 
drawn from Eriocarpum. 
I took what time I could to-day for the Gronovian 
plants and a few of Plukenet’s, ete., but was unable 
to finish; will go to-morrow, for I shall work to the 
last moment. 
T have been tempted to buy a collection of Hart- 
weg’s* very fine Mexican plants, which being col- 
lected far in the interior of north Mexico are very 
North American, and quite necessary, I think, for us. 
They will reach you with the other parcels. Be care- 
ful about the little labels with the numbers stuck on. 
Bentham will publish them presently. . . . 
1 Theodore Hartweg, died in 1871. Explored in Mexico and Cali- 
fornia, 1836 to 1847; later director of the Grand -ducal Gardens, 
Swetzingen, Baden. 
