368 VARIOUS PLANT GROUPS 



no special peculiarities. In lindens, however, the lowermost 

 bract of the flower-cluster is large, forming a sort of involucre, 

 and adheres for a considerable distance to the peduncle. 

 Jute flowers, which have the stamens in two whorls of five 

 each, thus conforming to the numerical plan of the other 

 floral organs, afford the simplest condition. In other species 

 the stamens appear to be indefinite in number, but close 

 examination would show them to be grouped into five clus- 

 ters opposite the five petals. Each cluster is taken to repre- 

 sent the branches of a single.one of the inner whorl of stamens, 

 in much the same way that a pair of long stamens in the 

 mustard family represent, as we have seen (section 110), a 

 single branched stamen. 



The fact that the stamen-groups are opposite the petals (hence 

 regarded as being of the inner stamen whorl) is expressed by placing 

 the sign 1 1 between P and FA. 



Stamens in five clusters are said to be pentad elphousA 

 The stamens of the linden are always pentadelphous, and 

 sometimes each cluster includes a staminode to which the 

 anther-bearing filaments are coalescent. Throughout the 

 family two pollen-sacs are borne by each filament which, 

 however, divides more or less at the tip into a short stalk 

 for each sac. 



The fruit of jute is a capsule dehiscing by dorsal sutures 

 into valves attached to the radial partitions. Such dehiscence 

 is called locuUcidal.^ In lindens onlj^ one of the five carpels 

 ripens, and commonly only one of the seeds which it contains. 

 The pericarp becomes somewhat drupaceous so that the 

 product of each flower resembles a small round almond. But 

 a cluster of these nut-like fruitlets is formed by each in- 

 florescence, and this cluster, borne on a common peduncle 

 to which the bract still adheres, separates at maturity as a 

 whole from the tree. The dry bract serves excellently as a 



' Pen"-ta-derphous < Gr. pente, five. FA oo -=- 5, 

 - Loc'u-li-ci"dal < L. loculus, a compartment; coedere, cut, because 

 it is as if each compartment were cut into, so that in cross-section each 

 division has a form something Uke the sign J_ which is used to distin- 

 guish this type of capsule in the formula of Corchorus. 



