sclb] 



flEije Er*a3uri) nf 3S0tani?, 



1038 



at the base by a membrane), and incon- 

 spicuous green flowers, of which the calyx 

 is contracted at the mouth, and becomes 

 rigid when in fruit. The segments of the 

 calyx are edged by a narrow white mem- 

 brane, which gives the flowers a variegated 

 appearance. There are two British spe- 

 cies— 8. annuus, the annual Knawel, a 

 common weed in cornfields; and S. peren- 

 nis, which scarcely differs except in having 

 perennial roots. French : Gnavelle ; Ger- 

 man : Wilde Knauel. EC. A. J.] 



SCLERIA. A genus of sedge-grasses be- 

 longing to the tribe Sclerinece. The inflo- 

 rescence is in spikes, male female or 

 androgynous; scales imbricated on every 

 side, the lower subdistichous and empty ; 

 stamens three, rarely one to two; female 

 spikelets one-flowered ; styles three-cleft ; 

 androgynous spikelets with the lowest 

 flower female, the others male. Steudel 

 describes 149 species, which have a wide 

 geographical distribution, chiefly within 

 or bordering on the tropics of the south- 

 ern hemisphere. [D. M.] 



SCLEROCHITOK A genus of Acantha- 

 cece, containing a single species from the 

 Cape of Good Hope. It is an erect uuder- 

 shrub, with small rigid suboval leaves, and 

 solitary axillary flowers. The persistent 

 calyx is five-parted ; the corolla has a 

 single lip with an incurved tube and five- I 

 lobedlimb; the four stamens are exserted, I 

 and the anthers consist of a single semi- i 

 ovate cell which has a ciliated margin ; the I 

 style is persistent; the stigma is bidentate; ' 

 and the capsule is two-celled, the lower 

 half compressed, the two seeds beinpr borne 

 above the middle. [W. C] 



SCLEROCHLOA. A genus of grasses 

 belonging to the Festucece, the species of 

 which are arranged by Steudel under Gly- 

 ceria, and by Bentham under Poa. [D. M.] 



SCLERODERMA. A genus of puffballs 

 with a hard coriaceous coat, which con- 

 tains a mass of spores here and there di- 

 vided by thin filmy partitions. In an early 

 stage the component threads produce 

 swollen sporophores.which bear about four 

 rugged spores on as many papilla?. The 

 threads except in the partitions soon va- 

 nish, and the spores seem to acquire their 

 full size and structure when free. In 

 general the peridium bursts irregularly at 

 the summit, but in S. Geaster it opens in a 

 stellate manner, exposing a globular mass 

 of seeds. & vulgare, which is neat sub- 

 globose and about the size of an onion, is 

 common in woods and on lawns, the sur- 

 face being variously cracked or warty. 

 Some of the species, when growing in sand, 

 and assuming a subterraneous habit, are 

 occasionally mistaken for truffles, but they 

 are too tough to be good articles of food 

 in any condition. One of them is subject 

 to be infested by Boletus parasiticus, which 

 is abundant in the pleasure-grounds at 

 Kew, though rare elsewhere. [M. J. BJ 



SCLEROGEN. The hard matter depo- 



sited by some plants in the interior of 

 their cells, as in those forming the shell of 

 the walnut. 



SCLEROGENEA. A condition in culti- 

 vated plants, consisting in a tendency to 

 revert to their natural condition, which is 

 indicated by a hardening of the tissues, 

 accompanied frequently by a diminution 

 of cellular development and of the nutri- 

 tious matters of which it is the object of 

 the cultivator to promote the formation. 

 It is in fact exactly analogous to what is 

 called grittiness in pears, which is ex- 

 hibited exactly in proportion to the ap- 

 proach of any especial variety to the wild 

 condition. It is the vascular bundles more 

 especially which are affected, and in con- 

 sequence such roots as carrots, beet, tur- 

 nips, &c, become almost uneatable, potatos 

 are stringy, and even fruits like apricots 

 (especially the variety called Breda) become 

 more or less disagreeable. This condition 

 may either belong to particular individuals 

 produced from seed, or it may be depend- 

 ent on peculiarly dry seasons or other con- 

 ditions unfavourable to rapid growth. The 

 cellular tissue or its richness in fecula is 

 not always affected. Stringy potatos, for 

 example, are sometimes more mealy than 

 others. This affection is totally different 

 from one in which the tissues are hardened 

 from an alteration in the structure of the 

 walls due to some chemical change, or 

 from the condensation of the contents of 

 the cells from some similar cause. Good 

 cultivation and well-selected seed are the 

 only remedies, and even these are not 

 always efficient. [M. J. B.] 



SCLEROID. Having a hard texture. 



SCLEROLOBIUM. A genus of Legumi- 

 nosce of the tribe Ccesalpinece, comprising 

 eight species of forest-trees peculiar to 

 Brazil and Guiana. They have alternate 

 equally pinnate leaves, and small yellow 

 odoriferous flowers, disposed in great pro- 

 fusion in large terminal racemed panicles. 

 The essential characters of the genus are : 

 a shortly tubular five-parted persistent 

 calyx ; five very narrow petals ; ten per- 

 fect stamens, their filaments free and 

 bearded at the base ; and a sessile ovary 

 which, when ripe, is a compressed ellipti- 

 cal woody pod with a few seeds. S. tincto- 

 rium has, according to Mr. Spruce, a rough 

 bark which abounds in tannin, and is used 

 as a dye about Caripi, in Brazil. S. chry- 

 sophyllum, so called from the golden-yellow 

 silky hairs on the uuder-surface of the 

 leaflets, is a North Brazilian species, grow- 

 ing to a height of sixty or a hundred feet. 

 Its white wood is used for making charcoal 

 and for other purposes. The name of the 

 genus alludes to the hard woody nature of 

 the pod, which does not open when ripe 

 like most others. [A. A. B.] 



SCLEROON. A genus of Yerbenaceas, 

 containing a single species from Mexico. 

 It is a shrub with opposite entire leaves, 

 and flowers in axillary few-flowered cymes. 

 The calyx is cam panulate andfour-toothed ; 

 the corolla funnel-shaped, with a quadrifld 



