212 



PHYTOTOMY. 



pollen from the bent antherae, and bring it to other blossoms 

 of the same species. Nor is there much danger of a mixture of 

 species, and a production of hybrids in this way, because it is 

 proved respecting bees at least, that in each excursion they 

 gather only from flowers of the same species ; (C. K. Spren- 

 gel, Entdecktes Geheimniss der Natur im Bau, und in der Be- 

 fruchtung der Blumen ; Berlin, 1793, 4to. Smith's Intro- 

 duction to Botany, ed. 3., p. 256, 257.) 



VII. On the Structure of the Sexual Organs. 



333. 



The analogy between the filaments and the petals, which 

 was formerly stated, (181. and 187.), as well as their fre- 

 quent union, lead us to conclude that the foniier have^ a 

 similar structure with the latter. Where the filaments are 

 so fine that they cannot be dissected, their structure, of 

 course, remains hidden from us. But in some of the greater 

 flowers among the Liliacea?, we meet with filaments of consi- 

 derable diameter ; and the filaments of the Malvaceae can also 

 be easily examined. In these instances, we obilrve that very 

 fine bundles of spiral vessels proceed through the whole length 

 of the filaments to their summits, and are so lost at their 

 points, that we cannot exactly point out their mode of con- 

 nection with the antherae. The filaments likewise contain a 

 very fine cellular texture, and have sometimes also a corollar 

 integument. 



This simple structure, however, varies according to the 

 manifold variations of the external form of the filaments. 

 Particularly, we observe in the Urticeae an articulated struc- 

 ture of the filaments, by means of which, in the Parietaritty 

 Forskolea^ and Antiaris, they are inclosed in the lobes of the 

 calyx, previous to their being fully ripened, and afterwards 

 spring forward with great elasticity to scatter the pollen from 

 the antherae. More minute experiments have not yet been made 

 respecting the internal structure of these joints in the fila- 

 ments. Meanwhile the contracted portions seem to occasion a 



