CALYCIFLOR.© 193 



of a tree whose leaves develop a sweet sugar sap or 

 honey-dew. Aphides or lice-like insects pierce the 

 tissues, and suck out the juice, and this forms the 

 honey-dew, of which ants are fond, and which they 

 receive in return for not molesting the aphides. The 

 aphis or " cow," on being tapped or *' milked " by 

 the ant, ejects upon the leaf the honey, which the 

 ants lick up. The honey-dew is hygroscopic, and 

 when dew falls it takes up the moisture, the honey- 

 dew forms a smear over the leaf, and, on evaporation, 

 this becomes a sort of varnish, which protects the 

 leaves from too rapid transpiration — a case in which 

 insects help to regulate the proper carrying out of a 

 vital physiological function. 



The Field Maple is common throughout the 

 country, especially in the south, and native up to 

 N. England, rare in Ireland. In Scotland it is 

 naturalised. It occurs in the Channel Islands. 



It grows in woods, thickets, and hedgerows. It is 

 found in oakwoods on clay and loam, in woods of 

 the sessile oak on siliceous soils ; on the chalk in 

 chalk scrub, in ash-oakwoods, on marls, and in the 

 marsh formation. 



Field Maple is a small tree, which when it attains 

 a good size is handsome, round-headed, and may 

 reach a height of 15 to 30 ft. The wood is used in 

 turnery. The foliage is dense, dark green. It is 

 often, however, only a small tree or bush in the 

 hedgerow. The branches are spreading. The bark 

 is corky, rough, and fissured. The wood is fine- 



13 



