DISCOPLEA. 



[ 267 ] 



DISTICHIUM. 



DISCOPLE'A, Ehr. A genus of Diato- 

 macese, not now retained, the species being 

 referred to the genera Cydotetta and Coscino- 

 discus. Ehr. Ber. Berl. Ak. 1844, p. 197. 



DISCORBI'NA, Parker and Jones. One 

 of the Rotalina, having a turbinoid spire, 

 with vesicular chambers, opening one into 

 another by slit-like apertures, which are 

 usually tented over by a succession of um- 

 bilical flaps, forming a star-like ornament 

 (see ASTERIGEBJNA). The shell is usually 

 coarsely, sometimes finely, and occasionally 

 partially porous. Fossil and recent. D. 

 rosacea (PI. 24. fig. 7 a, b) is a neat variety 

 of D. turbo. 



BIBL. Carpenter, Introd. For am. 203. 

 DISCO'SIA, Libert. A genus of Sphse- 

 ronemei (Stylosporous Fungi), probably re- 

 lated to some of the Sphceria, as stylospo- 

 rous forms. The species have been described 

 under various names ; and the genus Phlyc- 

 tidium of Notaris is synonymous with it. 

 The British species recorded seem to have 

 been greatly confused by different writers ; 

 for Discosia alnea. Libert, found on the 

 leaves of alder and beech , = Spharia arto- 

 creas, Tode, Xylomafagineum, Pers., Phlyc- 

 tidium nitidum, Wallr., Ph. clypeatum, No- 

 taris, and, from its name, we conclude also 

 Dothidea alnea, Pers. of Hook. Brit Flor., 

 with its synonyms. Fries, in his Summa 

 Veget., gives 2). artocreas, alnea, and cly- 

 peata as three distinct species. 



BIBL. Leveille, Ann. Sc. Nat. 3 ser. v. 

 286 ; Fries, Sum. Veget. 423 ; Fresenius, 

 Beitr. z. Mycol. Heft i. 66, pi. 8 ; De No- 

 taris, Mem. Accad. Torino, 1849, 2 ser. x. ; 

 Berk., Hook. Br. Fl. 278, 288. 



DISCOSIRA, Rab. A genus of Diato- 

 macee. 



Char. Frustules disk-shaped, concate- 

 nate ; valves nearly plane, with curved 

 costse ; margin denticulate ; centre deli- 

 cately punctate. 

 D. sulcata. Italy. 



BIBL. Rabenhorst, Flor. Alg. i. p. 36. 

 DISEL'MIS, Duj. = CHLAMLDOMONAS, 

 Ehr. ( Chi. pulviseulus, j.=Diselmisviridis, 

 D. ; PI. 7. fig. 2 b, c. ; PI. 30. group 30). 

 See PROTOCOCCUS. 



Dujardin describes a marine species, D. 

 marina. Body almost globular, obtuse and 

 rounded in front, granular within, and (from 

 generic characters) with a non-contractile 

 tegument and two similar cilia. 



"lie adds to this genus D. Dunalii=Mo- 

 nas Dunalii, Joly, giving rise to the red 

 colour of the reservoirs of the salt-works oi 



the Mediterranean ; oval or oblong, often 

 constricted in the middle ; colourless when 

 young, greenish when older, red when 

 adult ; no eye-spot. 



Probably marine Algae. 

 BIBL. Dujardiu, Inf. 340; Joly, Hist, 

 tfun Petit Crustace $c. 1840. 



DISIPHO'NIA, Ehr. D. australis (PI. 

 51. fig. \$) = Diatomella, pt. 



DISO'MA, Ehr. A genus of Infusoria, 

 of the family Enchelia. 



Char. Body double, not ciliated ; mouth 

 without teeth, ciliated and truncated ( = En- 

 chelys with a double body). 



I), vacillans (PI. 30. fig. 45). Segments 

 clavate, filiform ; hyaline and narrowed at 

 the anterior end; length 1-380 to 1-288". 

 In the Red Sea. 



BIBL. Ehr. In/us. 302. 

 DIS'SODON, Grev. and Arnott. A ge- 

 nus of Splachnacese (Acrocarpous opercu- 

 late Mosses), including some Splachna of 

 authors and a Cyrtodon. 



BIBL. Wilson, Bry. Brit. 295 ; Berkeley, 

 Handb. 163. 



"DISTEM'MA, Ehr. A genus of Rota- 

 toria, of the family Hydatinsea. 



Char. Eves two, cervical ; foot forked. 

 D. forfcula (PI. 43. fig. 25 ; fig. 26, teeth). 

 Body cylindrico-conical ; eyes red ; toes 

 strong, recurved, toothed at the base; fr. 

 water: length 1-120". 



Three other species, two of which are 

 freshwater, and one marine. In the latter, 

 D. marina, the cervical eye-spots are co- 

 lourless ; if these do not really represent 

 eyes, this species must be referred to the 

 genus Pleurotrocha. 



BIBL. Ehr. Infus. p. 449. 

 DISTIOHIA 'CE^E. A family of bpercu- 

 late Acrocarpous (terminal-fruited) Mosses, 

 of csespitose nabit ; the stem increasing to- 

 wards the point, simple or branched ; the 

 leaves with a dorsal keel-like nerve, equi- 

 tant-concave, densely imbricatively overlap- 

 ping, parenchvmatously areolated. Cells mi- 

 nute, with thick walls, somewhat papillose, 

 very densely packed, squarish. Capsules 

 oval, equal. British genus : 



DISTIC'HIUM, Br. and Schimper.-Ca- 

 lyptra dimidiate. Capsule annulate. Peri- 

 stome simple, with sixteen equidistant teeth, 

 free at the base, once or several times slit 

 from the base to the apex, trabeculate, deep 

 purple, homogeneous, smooth or rough. In- 

 florescence monoecious. 



BIBL. Wilson. Bry. Brit. p. 104 ; Berke- 

 ley, Handb. p. 266. 



