DIDYMOSPORIUM. 



[ 210 ] 



DINEMASPORIUM. 



barrel-shaped, longer than broad ; side view 

 circular ; angles bicrenate. (Sheath wanting 

 or indistinct.) 



The delicate longitudinal lines have been 

 proposed by Mr. Jenner as a test-object for 

 the power of the microscope ; they are best 

 seen in the empty cells when di-ied. Breadth 

 of filament, including teeth, 1-1030". 



D. Grevillii (PI. 10. fig. 5 ; fig. 6, side 

 view). Joints broader than long, with a 

 thickened border at their junction ; side view 

 broadly elliptic ; angles bidentate. (Sheath 

 distinct.) Breadth of filament 1-4/0", 



BiBL. Ralfs, Brit. Desmid. p. 55. 



DIDYMOSPORIUM, Nees.— A genus of 

 Melancouiei (Coniomycetous Fungi), grow- 

 ing upon shoots of trees. The only British 

 species, D. profusum, Grev., has very minute, 

 oblong, uniseptate spores, at first glued to- 

 gether like a depressed conical nucleus, be- 

 neath the epidermis, afterwards bursting 

 through, and becoming free. D. elevatum, 

 Jjk.=Melanconium bicolor, Nees. 



BiBL, Berk., Hook. Brit. Flor. v. pt. 2. 

 p. 357 ; Ann. Nat. Hist. vi. p. 438 ; Greville, 

 Sc. Crypt. Fl. pi. 212. fig. 1 (as Stilbospora). 



DIFFLUGIA, Leclerc— A genus of Infu- 

 soria, of the family Arcellina. 



Char. Contained in a si^herical or oblong, 

 urceolate carapace, from the anterior extre- 

 mitv of which are emitted variable, numerous 

 or multifid tentacular expansions. Aquatic. 



The carapace is membranous, often en- 

 crusted with minute grains of sand (and 

 carbonate of lime ?) ; in some it is covered 

 with depressions or tubercles ; these form 

 the genus Euglypha, D. The mode of repro- 

 duction has been observed in D. Enchelys, 

 which forms gemmae and also resolves itself 

 into four " spores." 



Species very numerous. 



D. proteiformis, E. (PI. 23. fig. 39). Cara- 

 pace oval or almost spherical, covered with 

 minute grains of sand; length 1-240". 



D. oblonga,^. {D.glohulosa {"?),!).) Cara- 

 pace oval, oblong, or rounded, smooth, 

 brownish; length 1-200". 



BiBL. Ehr. Infus. p. 130 ; Ber. d. Berl. 

 Akad. 1840, &c. ; Dujardin, Infus. p. 248; 

 Schkimberger, Ann. des Sc.nat.\^Ab. iii.254; 

 Schneider, Ann. Nat. Hist. 2nd ser. xiv. p. 332. 



DIGLENA, Ehr.— A genus of Rotatoria, 

 of the family Hydatinaea. 



Char. Eyes two, frontal ; foot forked. 



There are no other appendages than the 

 foot and the rotatory organ. 



Nine species. 



D.lacustris (n.34.figs.2\,22). Body oval, 



transparent, truncate in front ; foot suddenly 

 attenuate, somewhat more than l-4th of the 

 body in length ; toes l-3rd part of the foot in 

 length; aquatic; length 1-70". 



BiBL. Ehr. Infus. p. 441 ; Gosse, Ann. 

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



DILEPTUS, Duj.— A genus of Infusoria, 

 of the family Trichodina^a. 



Char. Body fusiform, prolonged anteriorly 

 in the form of a swan's neck, with a lateral 

 mouth at the base of the prolongation ; en- 

 tire surface covered with vibratile cilia, which 

 are more distinct in front and near the mouth. 



D. folium, D. (PI. 23. fig. 40). Body very 

 flexible, in the form of a lanceolate leaf, nar- 

 rowed in front ; with nodular, reticulated, 

 irregular ribs; aquatic; length 1-I60tol-I20". 



D. anser {Amphileptus anser, E.). 



D. margaritifer {Amphileptus marg., E.). 



Dujardin separates these species from the 

 genus Amphile])tus, on account of their not 

 possessing a reticulated integument like those 

 of the latter, and their consequently under- 

 going diflSiuence. 



BiBL. Duj. Infus. p. 404. 



DILOPHOSPHORA, Desm.— A genus of 



Fig. 180. 



Sphseronemei (Co- 

 niomycetous Fungi), 

 consisting of Sphce- 

 ria-like plants (with- 

 out asci), growing 

 upon the leaf-sheaths 

 and the glumes of 

 grasses; remarkable 

 for the curiously- 

 appendaged spores 



(fio-. 180). Dilophosphora graminis. 



D.graminis,'Y)Q^m. Spo'^^ magnified SOO diams. 



■=■ SphcBria Alopecuri, Fnes. Found m 

 France ; does not appear to have been met 

 with in Britain. 



BiBL. Desmazieres,y^wM. des Sc. nat. 2 ser. 

 xiv. p. 4. pi. 1. fig. 2. 



DINEMOURA, Latr.— A genus of Crus- 

 tacea, belonging to the order Siphonostoma 

 and family Pandaridse. 



Char. "Lamellar elytriform appendages 

 covering the thorax, only one pair. Three 

 first pairs of feet setiferous; the posterior 

 foliaceous and membranous. 



D. alata and B. Lamnoi have both been 

 found upon the Beaumaris Shark {Lamna 

 monensis). 



BiBL. Baird, Brit. Entomostr. p. 282. 



DINEMASPORIUM, Lev.— A genus of 

 Phragmotrichacei (Coniomycetous Fungi), 

 consisting of minute plants forming spots 

 upon the leaves of grasses. D. gramineum. 



