266 



BLACKTHORN 



Primus spinosa, L. Blackthorn (Fig. 97). Shrub with 

 thorns, and slender downy pubescent shoots, flowering 

 before the leaves open. Leaf 3 6 x 1 4 cm., ovate or 

 oblong-ovate, to obovate, obovate-lanceolate, elliptic or 

 broadly lanceolate ; tapering to the petiole, acute, irregu- 



Fig. 97. Blackthorn, Primus spinosa, p. 266 (Ett). 



larly and finely serrate or bi-serrate ; variable in size and 

 acuteness, those tufted on the dwarf shoots often obtuse. 

 Pubescent, or becoming glabrous above and pubescent 

 only on the veins beneath. Petioles 5 10 mm., eglan- 

 dular. Leaves convolute in bud. Autumn leaves yellow 

 to reddish. 



Venation pinnate-looped and reticulate. The midrib 



