M Y R 



AI Y T 



the Musophaga being the most conspi- 

 cuous of the group. 



MUSSEL BAND. The black shale 

 of coal mines, containing embedded 

 mussel-shells. 



MUSSITE. A pale green mineral 

 from Mussa, in Piedmont, consisting 

 of a variety of augite. 



MUSTE'LID^ {mustela, a weasel). 

 The Weasel tribe; a family of carni- 

 vorous vertebrata, which are mostly 

 semi-plantigrade, a portion of the sole 

 touching the ground. These animals, 

 owing to the length of theif bodies, and 

 the shortness of their limbs, are enabled 

 to insinuate themselves into small ori- 

 fices, and are hence called vermiform. 



MYADiE. Gaping Bivalves ; a family 

 of the macrotrachian bivalves ; named 

 from the genus mya, and having the 

 valves more or less gaping at one or both 

 extremities. 



MYCE'LIA (/iwKn?, a mushroom). The 

 rudiments of fungi, or the matter from 

 which fungi are produced. 

 MYELENCE'PH ALA (/Lll;€^6p, marrow, 

 h^necpaXov, the brain). A term applied by 

 Owen to the grand primary division Ver- 

 tebrata of the animal kingdom, compris- 

 ing animals which possess a brain and 

 spinal marrow. These are the Spini- 

 cerehrata of Grant. 



MYELONEU'RA (^lueXo?, marrow, 

 vtvpov, nerve). The name given by Ru- 

 dolphi to a group of animals correspond- 

 ing with the Articulata of Cuvier, which 

 have a ganglionic nervous system, form- 

 ing a cord considered analogous to the 

 spinal marrow of the Vertebrata. 



MY'IOTHE'RIN^ (^i/Ia.afly, Onpiii^, 

 to chase). Fly-chasers ; a family of the 

 Insessores or Perching birds, or the Ex- 

 curtrices of Macgillivray. The term is 

 synonymous with Muscicapidae. 



MYRIA'PODA (^luptop, innumerable, 

 TToi/f, TToSof, a foot). The first class of 

 the Biplo-gangliata, or Entomoida, com- 

 prising animals with articulated bodies, 

 all the segments of the trunk being pro- 

 vided each with one or two pairs of 

 jointed ambulatory feet. They are di- 

 vided into the two following orders by 

 the differences of their jaws and feet : — 



L Chilognatha, or those which have 

 solid cylindrical segments, antennae with 

 seven joints, two strong mandibles with- 



out palpi, and very short feet terminated 

 by simple ungues, as in the iulus. 



2. Chilopoda, or those in which the 

 segments are more soft and depressed, 

 and each furnished with a single pair of 

 feet ; the antennae have more than thir- 

 teen joints, and the mouth is furnished 

 with palpigerous mandibles, and with an 

 upper and lower lip, as in the scolopendra 

 morsitans. 



MY'RICIN. The ingredient of wax 

 which remains after digestion with alco- 

 hol. 



MYRISTICA'CE^. The Nutmeg tribe 

 of dicotyledonous plants. Trees with 

 leaves alternate ; flowers dioecious, with 

 no trace of a second sex ; fruit baccate, 

 dehiscent, 2-valved; seed nut-like, en- 

 veloped in a many-parted arillus. 



MY'RMELEO'NIDiE (M'''PM»if, an ant, 

 Xeo)!/, a lion). A family of Neuropterous 

 insects, named from the typical genus 

 myrmeleon, the larvae of wiiich, from 

 their peculiar habits, have acquired the 

 name of ant-lions. 



MY'RMOTHERINiE (wi^PM^f, an ant, 

 Onpdct), to chase). Myrmotherine birds, 

 or Ant-catchers ; a family of the Canta- 

 <rice* of Macgillivray, distinguished from 

 the Thrushes chiefly by their shortened 

 form. The only British species is the 

 Cinclus or Dipper. 



MYRO'NIC ACID (^ypoi/, an odorous 

 oil). A bitter acid procured from black 

 mustard seeds. 



MYRTACE^. The Myrtle tribe of 

 dicotyledonous plants. Trees or shrubs 

 with leaves opposite, entire, and marked 

 with transparent dots ; flowers polype- 

 talous ; stamens perigynous ; carpella 

 concrete; inferior ovarium with several 

 cells. 



M YSTACI'NE^ {nvara^, moustache). 

 A family of the Infusoria, including 

 those which have superficial cilia dis- 

 posed in groups. 



MYTILA'CE^. The Mussel tribe; 

 an order of the conchiferous MoUusca, 

 named from the mytilus, in which the 

 mantle remains open in front (at the end 

 where the mouth is situated), and closed 

 behind, an aperture being left for the 

 egress of the fluid. They have a foot 

 suflSciently strong for crawling, and com- 

 monly affix themselves by a byssus. 



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