^sculus 



21 I 



above the cotyledons the first pair of true leaves are produced, which are opposite, 

 compound, digitately five-foliolate, and closely resemble the adult foliage except that 

 they are smaller in size. Successive pairs of similar leaves follow on the stem, each 

 pair being placed decussately with reference to the pair immediately below it. 



Abnormal Flowering 



The horse-chestnut sometimes produces a second crop of flowers in autumn, 

 which appear in much smaller panicles than those of spring. This is due to the 

 premature fall of the leaves in July or August, usually following an excessively 

 dry season. The buds are stimulated to premature energy and put forth young 

 leaf-shoots, which are terminated by flowers. This phenomenon, which is equivalent 

 to an anticipation of the opening of the buds by several months, as they would 

 normally open in the following spring, is frequently observed in the trees planted 

 in the boulevards of Paris.^ In the dry season of 1884, a single tree at Kew 

 produced small panicles of flowers in September, after previously shedding nearly 

 all its leaves. In the following year it produced a few panicles of the ordinary 

 size. At Hythe,^ near Southampton, a horse-chestnut is reported to have bloomed 

 and fruited three times in 1868, once in spring, again after the rain which succeeded 

 the long drought, and a third time in September. 



Identification 



In summer the common horse-chestnut is unmistakable. The only other 

 species with large sessile leaflets, ^scuhis turbinata, is easily distinguished by their 

 regular crenate serration. In winter the twigs and buds show the following 

 characters : — Twigs stout, brown, glabrous or minutely pubescent towards the tip ; 

 lenticels numerous. The large opposite leaf scars, flat on the twigs with no 

 prominent cushion, are joined by a linear ridge, and vary in shape, the larger being 

 obovate with seven bundle-dots, the smaller semicircular or crescentic with usually 

 only five dots. Buds very viscid, larger than in the other cultivated species ; the 

 terminal much exceeding the lateral buds in size, occasionally absent, and replaced 

 by the saddle-shaped scar of the previous year's inflorescence ; scales imbricate, the 

 external ones in four vertical ranks, rounded at the apex, glabrous, not ciliate, dark 

 red-brown. The buds contain the next year's shoot in an advanced state of 

 development, flowers being visible in them in October. The scales are morpho- 

 logically equivalent to leaf-bases. In the interior of the bud, scales are observable 

 with traces of leaf-blades, which gradually pass into the true leaves, visible in the 

 upper part of the bud. 



Varieties 



I. Var. flo7'e plena, Lemaire, Ilhist. Horticole, 1855, ii. t. 50. A variety with 

 double flowers, the pistil even in some cases becoming petaloid. Mr. A. M. 



1 See article by Roze, translated in Card. Chron. 1898, xxiii. 22S. - Card. Chron. lS68, p. 11 16. 



