238 VEGETABLE ORGANOGRAPHY. 



appear to me to be a true involucrum with several leaf- 

 lets, inclosing sometimes the male, sometimes the female 

 flowers, and more rarely the two sexes together. 



The leaves of the involucrum, or the bracts of Mosses, 

 differ from the ordinary leaves nearly as the bracts of 

 phanerogamous plants, either in size, form, or even in 

 colour; frequently the middle nerve is absent when the 

 other leaves are furnished with it. At other times they 

 are prolonged into a long bristle, which is wanting in the 

 ordinary leaves ; sometimes those of the two sexes or 

 those of different rows differ from one another ; but 

 these leaflets are never verticillate as in the perigone or 

 calyx, but always imbricated as in involucra. 



In these capitula, whatever be the sex of the organs 

 they contain, are found an indefinite number of simple 

 divided filaments. Hedwig has given them the name of 

 Paraphyses ; they are most frequently cylindrical, and 

 longer than the sexual organs ; we find some which are 

 gradually thickened towards the apex, and others abruptly 

 dilated into an oval or globular kind of club. They 

 usually spring from very near the base of the sexual 

 organs. They have been compared to the nectaries of 

 flowers, but I have already shown in what a vague sense 

 this word was used ; I should be inclined to compare 

 them with the little scales found in the involucra of 

 Euphorbia, and to regard them either as bracteoles, or as 

 the rudiments of a true perigone. They continue for a 

 long time without changing their form, and their func- 

 tion, with regard to the fructification, is entirely un- 

 known. 



The male organs of Mosses are found scattered among 

 the paraphyses in an indefinite number : they entirely 

 compose the male capitula of the monoecious or dioecious 

 species, and surround the female organs in the herma- 

 phrodite capitula. Each of them is composed of a very 



