M IT 



301 



MOB. 



A plant which has only one coty- 

 ledon or seed-lobe. 



MONOCOTYLE'DONOUS. Plants, the seeds 

 of which have either only one 

 cotyledon, or if more, those alter- 

 nate on the embryo, are called 

 monocotyledonous ; grasses, lilies, 

 aloes, and palms, are examples. 

 Monocotyledonous plants may be 

 at all times recognised, from the 

 circumstance of the veins of their 

 leaves being parallel, while those 

 of dicotyledonous plants are reti- 

 culated. 



MONOS'CIA. (from povos, one, and 

 oiKia, a house, Gr.) The twenty- 

 first class of plants in the ar- 

 tificial system of Linnaaus. In 

 this class of plants the stamina 

 and pistils are in separate flowers, 

 but growing on the same individual 

 plant. The orders in this class 

 depend upon the circumstances of 

 their male flowers, and are nine or 

 ten in number. 



MONOB'CTOTJS. Plants belonging to the 

 class Monoecia. 



MO'NODON. (from /tovd^ove, Gr. hav- 

 ing one tooth.) The sea unicorn, 

 or narwhal ; distinguished by its 

 long tusk, or tusks, for there are 

 sometimes two, extended in a hori- 

 zontal direction. The Monodon 

 belongs to the order Cetacea, class 

 Mammalia. 



MONODO'NTA. A genus of univalve 

 shells separated from Trochus on 

 account of a tooth-like process 

 which it forms at its base. Several 

 fossil species are known in the 

 oolitic formations of England. 

 Lycett. 



MONOPE'TALOUS. (from ^toVos, one, 

 and 7rera\ov } a petal, Gr.) Flowers 

 are so called which consist of only 

 one leaf or petal; or when the 

 leaves whieh compose the corolla 

 are united by their edges ; the con- 

 volvulus, honeysuckle, &c., are 

 examples. 



MONOPHY'LLOUS. (from /toVos, sole, 

 and 0v\Xoj/, a leaf, Gr.) Having 



one leaf only, or formed of one 

 leaf; applied to calices consisting 

 of not more than one leaf. 



MONOSE'PALOTJS. A term applied to the 

 calyx of a flower, when the sepals 

 which compose it are united by 

 their edges : the pink, convolvulus, 

 henbane, &c., are examples. 



MONOTHA'LAMOUS. (from ^oVos, single, 

 and tfaXayttos, a chamber, Gr.) 

 Shells whose chamber is undivided 

 by partitions; these are termed 

 unilocular, or monothalamous : the 

 argonaut is an example. 



MO'NOTREME. The Monotremes form 

 Cuvier's third tribe of Edentata, 

 comprising two genera, namely, 

 Echidna and Ornithorhynchus. 

 They are foand only in New Hol- 

 land. The Monotremes seem con- 

 nected with the birds ; one genus, 

 the ornithorhynchus, having a 

 mouth resembling the bill of a duck, 

 and being almost web-footed; it 

 has also been stated to be oviparous. 

 The Monotremes have no marsupial 

 pouch. They suckle their young 

 from a mammary orifice. In the 

 classification of some authors, Mon- 

 otremata constitutes the second 

 order of the sub-class Implacen- 

 talia. 



MOO'NSTONE. A variety of felspar, 

 called also adula/ria, possessing a 

 silvery or pearly opalescence. 

 Moonstone is transparent and trans- 

 lucent : colour white, with some- 

 times a tinge of yellow, green, or 

 red. When held in certain posi- 

 tions, its surface is iridescent. It 

 occurs massive, and in crystals. It 

 is found in the fissures and cavities 

 of granite, gneiss, &c. 



MORA'INE. An accumulation of sand, 

 stones, or debris, found upon ice- 

 bergs, glaciers, &c. In front of 

 glaciers there is usually a pile of 

 rubbish, composed of pieces of rock, 

 earth, and trees, which they have 

 forced forward, known in Switzer- 

 land by the name of moraine. If 

 there be a line of moraine some 



