of tliem more or less two-lipped. The genus 

 consists of undershrubs or climbers, with 

 alternate entire or pi nnately divided leaves, 

 often terminating in a tendril, and solitary 

 terminal, pedunculate flower-heads. The 

 involucre, usually cylindrical, has broad im- 

 bricated scales, the receptacle naked, the 

 florets of the disk slightly irregular, with 

 long exserted anthers furnished at the base 

 with long points or tails, those of the ray 

 female and more distinctly labiate. The 

 pappus consists of long feathery bristles. 

 There are above thirty species, natives of 

 South America, and the greater number 

 confined to the Andes of the West and es- 

 pecially of Chili. Many of the species with 

 purple pink or yellow flowers, are highly 

 ornamental. 



MUTTY-PAL. A resinous exudation 

 from Ailantus malabaricus. 



MYAGRUM. A genus of Cruciferw, con- 

 sisting of erect glabrous annuals, growing 

 in sandy fields in South-eastern Europe. 

 The stem leaves are arrow-shaped and em- 

 bracing ; and the racemes elongate, spike- 

 like, with small pale yellowish flowers. The 

 pouch is indehiscent, of a corky texture, 

 compressed at the apex and attenuated at 

 the base, one-seeded. [J. T. SJ 



MYALL-WOOD. The hard violet-scented 

 wood of Acacia homalophylla. 



MYANTHUS. A spurious genus of or- 

 chids, now reduced to Catasetum, plants 

 having been found, as alreadv mentioned 

 under Monachanthus, bearing flowers of 

 the three supposed genera on one spike. As 

 a section it is distinguished by having the 

 two cirrhi at the base of the column, in- 

 stead of its apex as in Catasetum. [A. SJ 



MYCELIUM. A word equivalent to 

 spawn, denoting the vegetative part of 

 Fungi, the greater portion of what most 

 readily attracts notice being frequently 

 merely the fructification. The vegetative 

 part of a mushroom, for instance, is re- 

 presented by the delicate white down and 

 strings which traverse the soil ; the fruit 

 is the stem.pileus, and gills, which we call 

 the mushroom. The mycelium of Fungi is 

 sometimes filamentous, sometimes cellu- 

 lar, and has received different names in 

 different families. The mould-like web of 

 Sphceria aquila has not, however, more 

 title to notice than the indistinct appa- 

 rently scarcely organised stain of which 

 the spawn of Sphceria pulvis pyrius con- 

 sists. In chose cases, however, which are 

 apparently so obscure, if a thin slice of the 

 matrix be submitted to the microscope, 

 delicate threads will be found penetrating 

 the tissues in every direction. 



As the spawn of Fungi assumes various 

 forms, and may be dry or moist, fleshy or 

 filamentous, friable or gelatinous, and as 

 it frequently remains for a long time dor- 

 mant without producing fruit, a number 

 of spurious genera, as Himantia, Rhizomor- 

 phti, &c, have been introduced into sys- 

 tems, which it has taken the labour of 

 years to eradicate. Occasionally the spawn 



bears a kind of fruit, which has tended to 

 make a correct estimation of its nature 

 more difficult. The spawn of Sphceria Bes- 

 mazierii, for instance, in the absence of the 

 capsules, might be taken for a true mould. 

 Spawn may be either annual or perennial. 

 In the latter case it may ' run ' for years 

 without bearing fruit, till a favourable 

 season occurs, a fact which will account 

 for the apparently capricious growth of 

 many species. 



The spawn of our common mushroom is 

 raised artificially for sale by nurserymen. 

 Many attempts have been made to pre- 

 pare the spawn of truffles, but they have 

 as yet been unsuccessful. The introduc- 

 tion of the spawn of valuable varieties 

 of mushroom will, we have no doubt, some 

 day cause a considerable change in the 

 produce of the mushroom bed. [M. J. B.] 



MYCETALES. An important alliance 

 of cryptogams, consisting of Fungi and li- 

 chens, which are so closely allied, and so 

 distinct from other cryptogams, that in any 

 natural arrangement they must be placed 

 in one section. They derive nutriment 

 either from the matrix on which they grow, 

 as Fungi, or from the surrounding air, as 

 lichens. Algm are distinguished by their 

 deriving nourishment by their whole sur- 

 face from the water in which they are sub- 

 merged. There are, however, exceptions 

 in either case, and though there is seldom 

 the slightest difficulty in determining the 

 alliance to which each particular object 

 belongs, it is almost impossible to draw up 

 satisfactory general characters from fruit 

 or structure. Both lichens and Fungi pro- 

 duce a distinct spawn or mycelium, whereas 

 in Algce the new plant arises at once from 

 the spore. [M. J. B.] 



MYCINA. Such a shield as occurs in the 

 genus Bceomyces among lichens, 



MYCODERMA. A spurious genus, as- 

 signed sometimes to Fungi, sometimes to 

 | Algce.,_ consisting of a peculiar condition of 

 ■ certain moulds when developed in liquids, 

 j Common yeast is an example. [M. J. B.] 



MYCOLOGY. A name derived from two 



j Greek words importing a knowledge of 

 j Fungi. It is equivalent to the barbarous 

 word Fungology, which, like Muscology, 

 has been retained sometimes as a good 

 selling title, with a full sense of its incor- 

 rectness. Though Mycology in the first 

 instance regards simply the classification 

 of Fungi, no truly scientific man will be 

 content without ascertaining in some mea- 

 sure the properties of the subjects of his in- 

 vestigation. We consider ourselves bound, 

 therefore, in the present volume, to bring 

 forward more particularly those species 

 into notice which have some economical 

 value, or which are to be avoided as dan- 

 gerous. [M. J. BJ 



MYGALTJRTJS. A genus of grasses be- 

 longing to the tribe Festucece, now included 

 in the section Vulpia of Festuca itself. F. 

 uniglumis, or Mygalurus uniglumis, is a 

 small annual grass, which generally grows 



