THE SERVICE-TKEE. 



Py'rus tormina'lis Ehrh. 



In addition to the Apples and Pears and the Medlar 

 the genus Pyrus comprises some ten kinds of British 

 trees. To all of these the name Service-tree may be 

 applied, since they constitute the sub-genus Sorbus, 

 and the name " Service," which might be supposed 

 to be in some way connected with the Latin cerevi'- 

 sia, beer, is merely a corruption of Sorbus. Virgil 

 uses the word sorbum for a fruit, and Pliny men- 

 tions four kinds of tree under the name Sorbus, all 

 of which are probably members of the group as 

 now recognised by botanists. The characters of 

 the sub-genus are that the fruit is small, often 

 having less than five chambers, the styles being 

 accordingly from two to five in number, that the 

 core is brittle, and that the flowers are small, white, 

 and in branching, but flat- topped or " corymbose, 1 ' 

 clusters. The leaves may be simple, but are gener- 

 ally either deeply notched or pinnately compound. 



Of the ten British forms which have been 

 described, three only are at all commonly met with, 

 the Wild Service, P. torminalis Ehrh., the White 

 Beam, P. A'ria Ehrh., and the Rowan, Mountain 

 Ash, or Fowlers' Service-tree, P. Aucwpa'ria Ehrh., 

 the others being either slight variations, possible 

 hybrids, or trees of very local distribution. P. ru- 

 pic'ola Syme is closely allied to the White Beam, as 



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