246 



CHERRY, PHTM, ETC. 



scars in spirals ; the inner 

 scales, graduating to leaves, 

 fall later, leaving only the 

 typical stipulate leaves. 



It is generally difficult, 

 and sometimes extremely 

 difficult, to determine the 

 buds of the various species 

 of Primus and Pyrus and 

 allied genera. The green or 

 olive, fat buds, usually larger 

 at the apex, are characteristic 

 of Pyrus Aria, P. tormina- 

 lis, &c., but this does not 

 apply to the Rowan, Apple 

 and Pear ; the buds of Pru- 

 nus are usually more ovoid 

 or ellipsoid, with more 

 numerous matt-brown, dry 

 scales. A good general dis- 

 tinction is found in the leaf- 

 scars, which are usually nar- 

 row-crescentic and extended 

 some distance round the 

 twig in Pyrus (Fig. 59 g), 

 but semi-lunate or nearly 

 elliptical in Primus and 

 very slightly extended (Fig. 

 59 q). The periderm also 

 differs in the two genera, 

 and the exudations of gum, 

 so common in Primus, are 

 not found in Pyrus and 

 its allies : in Prunus the 



Fig. 129. Gean, Prunus 

 Avium, p. 244 (D). 



