180 BRITISH PLANTS 
the flowers, which are small, are clustered into head-like 
racemes. 
The spike (Fig. 77) and its variety, the catkin, are repre- 
sented chiefly by wind-pollinated plants—e.g., plantain, © 
hazel, alder, birch. Some grasses possess compound spikes. 
The orchids have stalkless flowers on an elongated axis, 
and, morphologically, these inflorescences are spikes ; 
but the usually long inferior ovary behaves as a stalk, 
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Fic. 77.—DIAGRAM OF Fig. 78.—WILLOW-HERB : LONGITUDINAL 
Spree. SEcTION oF FLOWER sHOWwING Lona, 
SvTaLK-LIKE INFERIOR OVARY (a). 
b, style; c, stigmas; d, stamens; 
e, petals; /, sepals. 
so that the flowers stand away from the axis, and 
biologically the inflorescence is a raceme. The same 
is true of the evening-primrose and some willowherbs 
(Fig. 78). 
The eyme (Fig. 79) is found in the Pink family and the 
valerians. The main axis ends in a flower, and one or 
two branches arise immediately below, which in their 
turn end in flowers. This method of branching continues 
until a large usually flat-topped inflorescence is produced. 
