82 ASSOCIATION OF ORGANISMS—THE WEB OF LIFE 
fly (Cyntps argentea) lays her eggs. The abnormal growths or 
“galls” which result from this process secrete nectar that serves 
to attract ants, and thus a body-guard is secured by which the 
attacks of caterpillars and snails are repelled. The following 
account is given by Kerner (in Zhe Natural History of Plants) 
of the way in which ants protect the flower-heads (capitula) of 
certain Composites:—‘‘ A similar state of affairs is met with on 
Fig. 1077.—A Saw-Wort (Serratula lycopifolia) defended by Ants (Formica ecsecta) against the attacks 
of a Beetle (Oxythyrea /unesta) 
the capitula of several Composites indigenous to South-eastern 
Europe, e.g. Centaurea alpina and Ruthenica, JSurinea mollis, and 
Serratula lycopifolia, the last of which is here figured [fig. 1077]. 
The young heads of these Composites are particularly liable to 
the attacks of voracious beetles, especially of Oxythyrea funesta, 
which bites big holes in them, destroying crowded flower-buds 
and involucral scales [z.e. the overlapping scales which surround 
the head] without the least difficulty. To meet this danger a 
garrison of warlike ants is employed. Honey is secreted from 
