M A D W O RT M A H O N I A. 



which means the constant deposition of osseous matter, 

 and its constant removal, can be shown by the alter- 

 nate layers of red and white in the bones, and the 

 subsequent disappearance of all adventitious colour, 

 when the use of madder as a food has been discon- 

 tinued for a sufficient length of time. It may be 

 proper to add, that the hardest part of the bones are 

 coloured in a f>w days. 



MAD WORT. Is the Alyssum saxatileof Linnaeus, 

 a numerous genus of annual and perennial herbs and 

 undershrubs natives of Europe. These herbs are, or 

 were supposed to be, useful against the effects of the 

 infection of canine madness. 



MAGGOT. The name given to the footless 

 larvae of some species of insects. See the articles 

 GRUB and INSECT. 



MAGILUS (Lamarck). This most extraordinary 

 mollusc, in its general appearance, might well be 

 mistaken for a fossil substance, or petrified body. It 

 is thick, ponderous, and resembling semi-transparent 

 alabaster. The apex of this shell is turned round 

 into a short oval spire, of about four whorls, resem- 

 bling the form of the Helix; these, as the animal 

 feels the necessity of extending its habitation, are 

 filled completely with testaceous matter, assuming 

 the appearance of a sculptured marble shell ; the last 

 whorl becomes prolonged by age in an irregularly un- 

 dulating, but nearly straight direction, deserting its 

 spiral turn ; and, as additions are made to its length, 

 the previous space occupied by the animal's body 

 becomes successively filled. We have, however, upon 

 one occasion observed several of these divisional 

 portions merely separated from each other, without 

 being rendered solid ; this circumstance is of very 

 rare occurrence. It is said that this tube some- 

 times extends several feet in length. This, by a 

 parity of reasoning, may be possible ; we have never 

 witnessed examples even one foot long ; and to all 

 nature's productions in this or any other branch, a 

 stage of perfection or completion of size is constantly 

 observable, and seldom varies to any great extent ; 

 though the sports of nature are not unfrequent. 

 The upper exterior part of this prolonged tube is 

 convex, the lower side flattened, plaited, carinated, 

 and somewhat angular, with closely set waved lamellar 

 plates, much thicker on one side than the other ; the 

 interior rounded, smooth, and its lower side with a 

 groove corresponding to the external keel. This 

 mollusc is doubtless closely allied to the Vermetus, 

 but yet nearer to the Siliquaria, from which it may be 

 said only to differ by possessing a closed keel, instead 

 of an open fissure. This shell, like the others men- 

 tioned, is not adherent, but merely enclosed in the 

 madrepore which forms its habitation. The animal of 

 this genus is quite unknown ; but, like that of the 

 Siliquaria and Vermetus, it is evident that it abandons 

 the spiral portion of its shell in proportion as it in- 

 creases in growth, augmenting the tubular portion, 

 and filling up almost constantly the space previously 

 occupied, while in its congeners a slight partition is 

 only formed between the periods of distance, and 

 forming as it were cells or chambers, which are never 

 perforated as in the Nautilacce. 

 . This mollusc is found imbedded in madrepore ; we 

 have only found it in the M. sinuosa, commonly 

 called the brain madrepore ; in this it is buried to a 

 considerable depth according to the size of the ma- 

 drepore, which sometimes is enormously large, as 

 may be witnessed by a magnificent specimen in the 



British Museum. In the early stage of the mollusc's 

 development, no more than the few spiral whorls are 

 imbedded, at which period a moderately long tube 

 would reach the surface ; but, in consequence of the 

 growth of the madrepore being in a semi-spherical 

 form, the animal of the Magilus, in order to keep 

 pace with it, from a necessity of having an open com- 

 munication to the exterior of its retreat, is forced to 

 abandon its first intention of forming spiral whorls, 

 which could never enable it to reach the surface, and 

 by prolonging the last one attains its object, that of 

 an exit at the nearest point. The waved lamellar 

 parts distinctly indicate the periodical removals of 

 the animal ; but nothing is known of the age of this 

 or other shells, from the impossibility of witnessing 

 their birth and growth in any one instance. The 

 M. antiqwu is the only species known, and it is- 

 generally found in the madreporic formations of 

 the Isle of France, and some parts of the Indian 

 Ocean. 



MAGNOLIACEjE. A natural order containing five 

 genera and thirty-seven species already described. The 

 order is divided into two tribes, viz. Illiciece and Magno- 

 liece. The first contains lllicium and Dr-imys, and the 

 second comprises Michclia, Magnolia, and Lirioden- 

 dron. The Magnoliea; and typical allies are splendid 

 shrubs or trees, with simple alternate leaves, and 

 convolute deciduous stipules, when young terminating 

 the branches with a conical calyptra, like those of 

 the fig, and when fallen leaving scars. The flowers 

 are terminal or axillary ; the flowers large, solitary, 

 and often intensely fragrant sometimes dangerously 

 so. The sepals are deciduous, and nearly entire ; 

 petals from three to many ; the stamens are indefinite 

 and borne on a rim seated below the germen ; the 

 filaments are three, anthers long, two-celled, bursting 

 longitudinally by clefts ; the ovaries are many, in an 

 imbricated series, each one-celled, one or more seeded, 

 seeds sometimes suspended ; the styles are short, and 

 the stigmata simple. 



The Magnolicce are all highly ornamented. The 

 hardy species from North America, and the more 

 tender ones from Eastern Asia, are among the most 

 interesting plants of our gardens. The Illicit-da:, like 

 the preceding, are aromatic bitters ; as examples, the 

 Drimys Winteri, the Tcrnus moschata, and the lllicium 

 anisatum, may be mentioned. The former yields the 

 true Winter's bark, which was found so beneficial a 

 restorative to the crew of Captain Winter's ship, who 

 accompanied the circumnavigator Drake. 



MAHOGANY TREE. Is the Swietenia maho- 

 gani of Linnaeus. East and West Indian timber trees, 

 of which great quantities from Honduras are annually 

 imported into Europe for the construction of house- 

 hold furniture. Young plants are kept in our stoves 

 as a curiosity, and are raised by cuttings. 



" The Honduras mahogany is less beautiful than 

 the Jamaica wood ; and it is not improbable that 

 they are the produce of trees specifically distinct. 

 About twenty thousand tons of mahogany are annu- 

 ally imported into this country : and a few years 

 since Messrs. Broadwood gave the enormous sum of 

 three thousand pounds for three logs of mahogany, all 

 cut from the same tree. The duty on mahogany 

 produces a revenue of nearly sixty thousand pounds 

 per annum." Burnett. 



MAHONIA (Nuttal). A genus of shrubs nearly 

 allied to Berbcr'ix, natives of North America, belonging 

 to the sixth class of Liimicus, and to the natural order 



