ORXITHOBIUS. 



[ 559 ] 



ORTHOTRICHUM. 



Hermannia. Cephalothorax soldered to 

 abdomen ; tarsi with 1 claw. 



Eremceus. Cephalothorax simple ; tarsi 

 with 3 heterodactyle claws. 



Damceus. Cephalothorax ribbed, legs 

 longer than the body, 1 claw. 



Galumna. Abdomen subglobular, de- 

 pressed, margins of the pseudothorax 

 winged ; legs of moderate length. 



Hoplophora. As the last, but wing-like 

 appendages absent ; tarsi 1-clawed. 



BIBL. Walckenaers Apteres, 251 ; Koch, 

 Deutschl. Crustac. ; Duges, Ann. Sc. Nat. ii. 

 48 ; Dufour, Ann. Sc. Nat. 1 ser. xxv. 289 j 

 Nicolet, Archiv d. Museum, 1855 ; Michael, 

 M. M. S. 1879, 225, 1880, 32, 177. 



ORNITHO'BIUS, Denny. A genus of 

 Anoplura. Like Nirmus, but with 2 horns 

 to the clypeus. O, cygni, on the swan ; 2 

 other species. 



OROBIAS, D'Eichwald. A Nummuline 

 or Fusuline Foraminifer, found in the Car- 

 boniferous Limestone of Russia ; possibly a 

 true Nummulina. 



BIBL. D'Eichwald, Leth. Ross. i. 352. 



ORTHOCERFNA, D'Orb. A Sticho- 

 stegian Foraminifer, related to Nodosarina ; 

 square or triangular in cross section; without 

 septal furrows ; orifice terminal, simple or 

 pouting. 



Recent in W. Indies, O. quadrilatera (PL 

 23. fig. 36) ; fossil in the Tertiary, Chalk, 

 Gault, and Oxford Clay. 



BIBL. Carpenter, For. 166. 



OR'THOCLASE. See ROCKS. 



ORTHODON'TIUM, Schwagr.,=5n/wra, 

 pt. O. gracile, on sandstone rocks. (Wilson, 

 Bryol. Brit. 218.) 



ORTHOP'TERA. An order of Insects, 

 containing the grasshoppers, crickets, &c. 



ORTHOSI'RA, Thw. See MELOSIRA. 



ORTHOTRICHA'CE^E. A tribe of 

 Pottioid Mosses including several British 

 genera. 



a. Papillae, distinct, tuberculate, rarely obso- 

 lete ; peristome mostly pale, rarely orange- 

 coloured. 



Zygodon. Calyptra dimidiate. Peristome 

 wanting, simple, external or internal, more 

 rarely glabrous, without an annulus. 



Orthotrichum. Calyptra campanulate, 

 plaited. Peristome absent, simple, or 

 double. External of thirty-two geminate 

 (sixteen, fig. 483) or bigeminate (eight, 

 fig. 537) teeth, more rarely of sixteen entire, 

 undivided teeth, granular, fleshy or brittle, 

 mostly pale, rarely orange-coloured, erect, 



afterwards reflexed, arising below the mouth 

 of the capsule. Internal : eight or sixteen 

 cilia, simple, hyaline, or rarely resembling 

 the teeth. Vaginule ochraceous. In- 

 florescence monoecious or dioecious. Capsule 

 without an annulus, pyriform, grooved, 

 rarely glabrous; operculum capitate, conical. 



b. Papilla mostly obsolete, rarely distinct] 

 peristome always coloured, purple, red, or 

 orange. 



Glyphomitrium. Calyptra campanulate, 

 large, totally enclosing the capsule, deeply 

 laciniate, plaited. Peristome of sixteen 

 short, lanceolate, densely trabeculate, entire 

 teeth, with a central line, in pairs, incurved, 

 arising below the orifice, orange-coloured, 

 smooth (fig. 283, p. 360). Inflorescence 

 monoecious. 



Brachystelium. Calyptra as in the pre- 

 ceding, entirely or almost covering the cap- 

 sule, mitre-shaped, with long and repeated 

 laciniations, slightly plaited. Peristome as in 

 Trichostomum, the teeth more or less split 

 to the base into two arms. Inflorescence 

 monoecious. 



Guembelia. Calyptra dimidiate, otherwise 

 like the following (figs. 289-291, p. 366). 



^ Grimmia. Calyptra mitre-shaped, laci- 

 niate, smooth, scarcely exceeding the oper- 

 culum, or shorter. Peristome simple, teeth 

 sixteen, lanceolate, with a median line, 

 trabeculate ; often, however, fissile, hence 

 very polymorphous, more or less split as far 

 as the middle into two or four teeth, or into 

 two arms down to the base (fig. 288, p. 365). 

 Fig. 536. Fig. 537. 



^T 



Fig. 6bti. Orthotrichum pulchellum. Mara. 15 diams 



Fig. 537. Orthotrichum pallens. Fragment of peri- 



etome. Magn. 50 diams 



ORTHOT'RICHUM, Hedwig._A genus 

 of Orthotrichaceae (Pottioid Mosses), grow- 

 ing in round tufts, fertile at the summit, on 



