MOTH, CLOTHES. 



[ 517 ] 



MOUTH. 



Sachs, Bot. 359; Janczewsky, Bot. Zeit. 

 187i>. 



MO'JII, CLOTHES. See Tinea. 



MOTHEK CELL, or Parent cell, the 

 term coimiu)nly applied to the cell in the 

 interior of which a new generation of cells 

 is developed. 



MOTHER-OF-PEARL. See Shell. 



MOUGEO'TL\.— A genus of Zyguema- 

 eejB (Confervoid Algae), distinguished by 

 the conjugation of the filaments taking place 

 without the formation of transverse pro- 

 cesses, the conjugating filaments being ge- 

 niculately bent. There is stih obscurity as 

 to the mode of reprodnction of the plants of 

 this genus. According to Vaucher, a spore 

 is formed iu one of the conjugating cells, 

 without transfer of contents, and this, ger- 

 minating in situ, breaks out from the pa- 

 rent cell. Hassali says the plants are re- 

 produced by zoospores ; this has been con- 

 firmed by "Kiitzing, who, together with 

 Itzigsohn", has observed the formation of 

 small rounded resting-spores iu the joints, 

 Avhich underwent segmentation and deve- 

 loped a number of smaller cells, the ultimate 

 fate of which was not observed. All this 

 tends to prove that the reproduction agrees 

 with that of Spirociyra, where we have : — 

 1. large conjugation-spores, sometimes ger- 

 minating hi situ, producing iu some cases 

 new filaments, in others zoospores ; 2. zoo- 

 spores produced immediately from the con- 

 tents; and 3. what appeared to be encysted 

 forms of these (see Spirogyea). 



M. genufexa, Ag. (fig. 139, p. 205). The 

 cells are about 1-72U" in diameter in 

 large specimens {M. major, Hass.), and 

 about three or four times as long ; iu smaller 

 specimens (J/, gemijiexa, Hass., M. (/racilis, 

 Kiitz.) the diameter is about 1-200", the 

 le.igth of the cells five or six times as great. 



In fig. 139 the lowest filament does not 

 belong to the genus; but the method of 

 conjugation of Mougeoiia is seen iu the one 

 above. 



AI. l(svis, Archer, is an Irish form. 



BiBL. \^aucher, Conf. creau douce, 79, 

 pi. 8; HassaU, Alg. 171, pi. 40; Kutz. Sj). 

 Alg. 43; Tah. Fhyc. v. pis. 1-3 and 36; 

 Itzigsohn, ^oi!. Zeit. xi. 081, 1853; Rabenh. 

 Ah/, iii. 255 ; Archer, Qu. Mic. Jn. 1867. 



MOULDS and MILDEWS. — These 

 names are generally applied indifferently to 

 a multitude of Hyphomycetous,_ Phycomy- 

 cetous and Coniomycetous Fungi ; but some 

 of the more common ones are especially 

 distinguished. Thus ordinary ' blue mould ' 



of cheese, &c. is Aspergillus glaucus; 

 another still more common blue or green 

 nioidd is Penicillium glaucum ; various 

 species of Oidium and Erysiphe are known 

 as the mildews of the Hop, Vine, Rose, 

 &c. The mildew of wheat is Puccinia. 

 graminis. 



MOUNTING. See Preservation. 



MOUSE, HAIR OF (PI. 1. fig. 3 ; PI. 29. 

 figs. 27, 28). See Hair of Animals and 

 Test-objects. 



MOUTH. — The mucous membrane of 

 the mouth, which becomes continuous with 

 the skin at the lips, is furnished with very 

 numerous conical or filamentous papiUse 

 resembling those of the skin, sometimes 

 simple, at others branched, and a number 

 of mucous glands. 



Its epithelium is of the pavement kind, 

 consisting of several layers of delicate cells ; 

 these are roundish in the deeper, flattened 

 and polygonal in the superficial layers. 



Fig. 492. 



Epithelial cells of the mucous membrane of the human 

 mouth : o, large, 6, smaller cells ; c, one with two nuclei. 



Magnified 350 diameters. 



The glands, distinguished, according to 

 their situation, as the labial, the buccal, and 

 the palatal glands, are rounded, about 1-36 



