MONOSTROMA. 



[ 431 ] 



MOSSES. 



guished by its definite, linear, convoluted 

 frond, enclosing a single moniliform filament. 

 It might readily be mistaken for a Nostoc 

 if superficially observed, but its convoluted 

 frond is devoid of the common membranous 

 pellicle. The only known British species is 

 Monormia intricata, Berk. 



This plant occurs in gelatinous masses, 

 each about as large as a walnut and of a red- 

 dish-brown colour, floating in slightly 

 brackish ditches. When the spermatic cells 

 are quite mature, the definite outline of the 

 linear frond is almost lost, and there is 

 little to distinguish the plant from Trichor- 

 mus, except the peculiar convolutions of 

 the moniliform filament; the frond then also 

 assumes a greenish tint. 



BIB L. Berkeley ( Gleanings of Brit. Algce, 

 t. 18) ; Ralfs, Ann. Nat. Hist. ser. 2. vol. v. 

 pi. 8. fig. 1 ; Harvey, Phyc. Britann. t. 256 ; 

 Hassall, Brit. Fr. Alga, t. 75. fig. 11. 

 Nostoc intricatum, Meneghini; Anabaina 

 intricata, Kiitzing, Tabula Phycologicce, 

 vol. i. t. 94. fig. 1. 



MONOSTROMA, Thuret. A genus of 

 Ulvaceae (Confervoid Algae), of which M. 

 bullosa (Ulva bullosa, Roth.) is the type, 

 distinguished from Ulva by consisting only 

 of a single layer of cells, and these being 

 roundish (mostly grouped in fours), im- 

 bedded in an apparently homogeneous gela- 

 tinous membrane (PI. 5. fig. 1 a). This 

 plant is reproduced by zoospores formed 

 from the cell-contents, and discharged by 

 bursting of the cell- wall (fig. 1 b, c). They 

 have four cilia. 



BIBL. Thuret, Ann. des Sc. nat. 3 ser. 

 xiv. p. 225. pi. 21. figs. 1-4; Note sur les 

 Ulvacees, Mem. de la Soc. Scient. de Cher- 

 bourg, ii. p. 1 (1854). 



MONOSTYLA, Ehr. A genus of Rota- 

 toria, of the family Euchlanidota. 



Char. Eye single, cervical; tail-like foot 

 simply styliform ; carapace depressed. 



Four species, three Ehrenberg, and one 

 other, Gosse. 



M. quadridentata (PL 35. fig. 11). Cara- 

 pace yellowish, fore-part of head deeply 

 cleft into four horns. Aquatic. Length 

 1-120". 



BIBL. Ehrenberg, In/us, p. 459 ; Gosse, 

 Ann. Nat. Hist. 1851. viii. p. 200. 



MONOTOSPORA, Corda. A genus of 

 Sepedonei (Hyphomycetous Fungi), of which 

 one species has been found in England, 

 growing on dead bark of the yew. M. mega- 

 lospora, Berk, and Br. Filaments erect, 

 simple, straight, nearly equal, articulated. 



Spores terminal, obovate, even, '0014 to 

 00133" long. Fries regards this genus with 

 doubt. 



BIBL. Berk, and Broome, Ann. Nat. Hist. 

 2 ser. xiii. p. 462. pi. 15. fig. 11; Fries, 

 Summa Veget. 497. 



MONURA, Ehr. A genus of Rotatoria, 

 of the family Euchlanidota. 



Char. Eyes two, frontal; foot simply 

 styliform. Carapace somewhat compressed 

 and open beneath. 



Two species. 



M. dulcis (PL 35. fig. 12). Carapace 

 ovate, obliquely truncate and acute behind ; 

 eyes distant. Aquatic. Length of carapace 

 1-280". 



BIBL. Ehrenberg, Infus. p. 474. 



MORELS. Species of Morchella, Dill. 

 (Ascomycetous Fungi), having a pileiform 

 receptacle, with a ribbed and lacunose hy- 

 menium on the upper side, bearing asci. 



MORPHIA. See ALKALOIDS, p. 25. 



MORPHO, Fabr. A genus of Exotic 

 Lepidopterous Insects. 



M. Menelaus. The scales from the wings 

 of this beautiful insect are sometimes used 

 as TEST-OBJECTS. 



MOSSES, MUSCACE.E. This order of 

 flowerless plants is distinguished from the 

 Hepaticaceae by the vegetative structure, or 

 by the sporange. In one group alone (Hy- 

 popterygiece) is the stem clothed with leaves, 

 accompanied by amphigastria (stipule-like 

 leaflets), in the manner of the foliaceous Hepa- 

 ticaceae (fig. 359, p. 337); and here the sporange 

 is a stalked urn-shaped body, with a deciduous 

 lid, and like those of the Mosses generally; 

 and this Jungermannia-like leafy stem is 

 erect, and not procumbent, as in Junger- 

 mannia itself. In all other Mosses the leaves 

 clothing the stem are arranged in a spiral 

 order around the stem, so as to give the 

 vegetative structure a very characteristic 

 aspect. 



The stem of the Mosses is a slender, 

 thread-like or wiry structure, wholly com- 

 posed of cellular tissue, without vessels, but 

 the external layer has an epidermoid cha- 

 racter, while the central portion is composed 

 of elongated cells. In one section of the 

 Mosses this stem terminates in a sporange, 

 and these are called Acrocarpous Mosses ; in 

 others the sporanges spring from lateral 

 branches, and the terminal bud of the stem 

 elongates the stem year after year; these 

 latter are called Pleurocarpous Mosses. 



The leaves are of simple structure, usu- 

 ally composed of a single layer of cells, the 



