379 



CIjc Crcafiuvp of 23otaitin 



[D^MO 



it differs only in having the wall? of the 

 fruit fleshy. It contains two Indian herbs 

 with weak stems climbing by means of 

 tendrils, compound triternate leaves, and 

 racemes opposite the leaves. [J. T. S.] 



DACTYLIS. A genus of grasses belong- 

 ing to the tribe Festucece, and distinguished 

 by the flowers being in very crowded 

 panicles, and subsecund, i. e., pointing 

 I nearly all to one side. The glumes are 

 unequal and many-flowered, acute and 

 '■ herbaceous, with terminal setae. B. glo- 

 meruia, the Cock's-foot Grass, is the only 

 i British species, and one of the best known 

 I of our native grasses. It is also the 

 i strongest grower among the superior 

 ; kinds, and derives its English name from 

 the fancied resemblance the three-branched 

 panicles of flowers bear to the foot of a 

 | fowl. It forms a portion of most good 

 pastures, particularly where the soil is 

 ' loamy or chalky. It is also suitable for 

 sowing alone on boggy land which is in 

 the course of being reclaimed, for, although 

 it does not grow on this sort of soil natu- 

 rally in great quantities, it produces a good 

 crop when cultivated on it artificially 

 Steudel describes twenty-nine species, 

 which have a wide' range of habitats over 

 the globe. [D. MJ 



DACTTLTUM. A genus of filamentous 

 moulds, of which the genuine species have 

 hyaline threads bearing at their tips clus- 

 ters of septate spores. B. rosewit, which 

 was formerly referred to Trichothecium 

 from an insufficient knowledge of its 

 structure, belongs essentially to this ge- 

 nus, and is remarkable not only as being 

 one of the most widely-diffused species, 

 distinguished by its delicate pink hue, but 

 as occurring not unfrequently in the closed 

 cavities of nuts. The spawn of these deli- 

 cate moulds will, however, soon penetrate 

 the firmest vegetable tissues if there be 

 proper conditions of moisture. Another 

 species, B. oogenum, occurs in the inside of 

 eggs, where its presence is difficult to ac- 

 count for without having recourse to the 

 wild and unphilosophical notion of equivo- 

 cal generation. In B. roseum, besides the 

 common large spores, there are conidia of 

 a small size, which may have greater power 

 of penetration than the larger. The func- 

 tion, however, of these bodies is uncertain, 

 and they may be spermatia rather than 

 conidia. [M. J. B.] 



DACTYLOCTEXIUM. A genus of grasses 

 belonging to the tribe Chloridece, distin- 

 guished by the inflorescence being in 

 finger-like spikes, the flowers on the spik- 

 lets pointing to one side; the glumes two, 

 compressed, keeled, and subherbaceous, 

 the exterior one cuspidate ; stamens three ; 

 ovary smooth ; styles two ; stigma hairy 

 and branched. There are only seven spe- 

 cies described, all natives of Africa^ with 

 one exception, B. radulans, which is a New 

 Holland grass. They are mostly annuals, 

 and little known in cultivation. [D. M.] 



D ACTYLORHIZA. An affection of some 



agricultural plants, as turnips and carrots, 



' in which the root divides and becomes 

 hard and worthless. It is commonly called 

 Fingers and Toes, and must be distin- 

 guished from anbury, which arises from 

 the attacks of insects. It is in fact not 

 properly a disease, but a tendency to a 

 reversion to the wild state, which can only 

 be remedied by a careful selection of seed. 

 It is sometimes thought that it arises f nun 

 an unequal distribution of manure, but 

 this is probably a mistake. [M. J. B.] 



1 DACTYLOSTEMON. A genus of the 

 spurge-wort family, composed of a num- 

 ber of trees or shrubs found in the tropical 

 parts of South America, and chiefly distin- 

 guished by their flowers being destitute of 



( a true calyx, the males containing three, 

 or more generally from four to seven sta- 

 mens. The leaves are lance-shaped, entire, 

 and glossy; either alternate or whorled, 

 and varying from two to eight inches in 

 length. In their axils the little green 

 flowers are arranged in short catkins, the 

 males towards the apex, and the females j 

 near the base, the former entirely naked I 

 or accompanied with one or more little j 

 scales which represent the calyx, the latter 

 also naked or having a calyx of three small 

 divisions. The fruit is a brown polished ; 

 three-lobed woody capsule, about the size 

 of a pea, and contains three seeds. The 

 name Actinostema< is sometimes given 

 to the plants of this genus. [A.A.B.] 



DJEDALEA. A genus belonging to the 

 spore-bearing section of the higher Fungi. \ 

 In this genus the cavities, instead of being 

 circular or only slightly distorted, are sin- 

 uous and intricate from the partial break- 

 ing-up of the cell-walls. B. quercina, a fun- 

 gus of a hard corky texture, is not un- 

 common upon oak stumps or rails, and 

 sometimes makes its appearance in build- 

 ings or conservatories, where the wood 

 has been impregnated with its spawn be- 

 fore being felled. [M. J. B.] 



D.EDALETJS. Wlien a point has a large 

 circuit, but is truncated and ragged. Or, 

 wavy and irregularly plaited as the hyme- 

 nium of some agarics. 



D^-EMONOROPS. A genus of palms 

 closely allied to Calamus, in which the 

 greater number of the forty species re- 

 ferred to it were formerly placed. Its dis- 

 tinguishing peculiarities consist in the 

 flowers being loosely scattered along the 

 branches of the flower spikes, not collected 

 into catkins as in Calamus, and also in the 

 spathes or bracts being complete, i.e., i 

 entirely enclosing the young spikes. All 

 the species are natives of the eastern 

 hemisphere, principally of the Malayan 

 Peninsula and Islands : they have long thin 

 flexible stems, furnished with pinnate 

 leaves, the prickly stalks of which are fre- 

 quently prolonged into whip-like tails. 



B. Braco (formerly Calamus Braco) is a i 

 native of Sumatra and other islands of the 

 Indian Archipelago, and is called the Dra- 

 gon's Blood Palm, in consequence of its I 

 fruits yielding a portion of the substance j 

 known in the arts as dragon's blood. The : 



