MOTH, CLOTHES. 



[ 517 ] 



MOUTH. 



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

 1872. 



MOTH, CLOTHES. See TINEA. 



MOTHER CELL, or PAHENT CELL, the 

 term commonly applied to the cell in the 

 interior of which a new generation of cells 

 is developed. 



MOTHER-OF-PEARL. See SHELL. 



MOUGEO'TIA. A genus of Zygnema- 

 cese (Confervoid Algas), 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 still obscurity as 

 to the mode of reproduction of the plants of 

 this genus. According to Vaucher, a spore 

 is formed in one of the conjugating cells, 

 without transfer of contents, and this, ger- 

 minating in situ, breaks out from the pa- 

 rent cell. Hassall 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 re sting-spores in the joints, 

 which 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 Spirogyra, where we have : 

 1. large conjugation-spores, sometimes ger- 

 minating in situ, producing iii 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 SPIROGYRA). 



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

 cells are about 1-720" in diameter in 

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

 about three or four times as long ; in smaller 

 specimens (M. gemtflexa, Hass., M. gracilis, 

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

 length 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 Mougeotia is seen in the one 

 above. 



M. leer's, Archer, is an Irish form. 



BIBL. Vaucher, Conf. d'eau douce, 79, 

 pi. 8; Hassall, Alg. 171, pi. 40; Kiitz. Sp. 

 Alg. 43 5 Tab. Phyc. v. pis. 1-3 and 36; 

 Itzigsohn, Bot. Zeit. xi. 081, 1853 ; Rabenh. 

 Alg. 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 

 mould 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 (PL 1. fig. 3 ; PL 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 papilla3 

 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. 



Epithelial cells of the mucous membrane of the human 

 mouth : a, 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 



