10 VEGETABLE ORGANOGRAPHY. 



If now, instead of studying the formation of the 

 raceme in a single stem, we examine what happens in 

 the branches of a branching one, we shall find evidently 

 that each of them may present the same phenomenon, 

 and as the branches spring from the axils of leaves, 

 axillary racemes will thus be formed. These kinds of 

 racemes then are only floral branches : sometimes they 

 bear also at their base a certain number of leaves, which, 

 having no flowers in their axils, retain their natural 

 forms, and then they are considered as so many distinct 

 racemes, or we are contented to say, that the plant 

 bears several ; sometimes towards the base they have 

 their leaves provided with flowers and changed into 

 bracts, so that the axillary raceme is without leaves, 

 properly so called, then the whole is considered as a 

 single inflorescence, and the name of Compound Ra- 

 ceme is given to it. Thus all racemes which spring 

 from the axils of leaves only differ from terminal ones 

 in their being placed at the top of a branch instead of a 

 stem. Their flowers arise from the axils of bracts, or 

 floral leaves, and the whole branch from the axil of a 

 leaf. 



All that we have said in taking the raceme for an 

 example is applicable, with very slight differences, to the 

 different kinds of indefinite inflorescence which we are 

 now about to pass rapidly in review, viz. — the Spike, 

 the Raceme, the Umbel, and the Capitulum, with the 

 varieties of each. 



1st. The name of Spike (spica) is given to those 

 indefinite inflorescences where the flowers arise from the 

 axils of leaves, either sessile, or borne upon a scarcely 

 visible pedicel, as, for example, in the Plantain. The 

 limit between the spike and raceme is very uncertain, 

 seeing that it only rests upon an appearance ; in fact, 

 the pedicel always exists, and its length alone is 



