DIDYMOSPORIUM. 



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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 dried. Breadth 

 of filament, including teeth, 1-1030". 



D. Gremllii (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 1-470". 



BIBL. Ralfs, Brit. Desmid. p. 55. 



DIDYMOSPORIUM, Nees. A genus of 

 Melanconiei (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 spherical or oblong, 

 urceolate carapace, from the anterior extre- 

 mity 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 Eugfypha, 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,~Ei. (D.globulosa (?),D.) Cara- 

 pace oval, oblong, or rounded, smooth, 

 brownish; length 1-200". 



BIBL. Ehr. In/us, p. 130 ; Ber. d. Berl. 

 Akad. 1840, &c. ; Dujardin, In/us, p. 248 ; 

 Schlumberger, Ann. des Sc. nat. 1 845. iii. 254 ; 

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



DIGLENA, Ehr. A genus of Rotatoria, 

 of the family Hydatinsea. 



Char. Eyes two, frontal ; foot forked. 



There are no other appendages than the 

 foot and the rotatory organ. 



Nine species. 



D. lacustris (PI. 34. figs. 21 , 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 Trichodinsea. 



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 l-160tol- 120". 



D. anser (Amphileptus anser, E.). 



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



Dujardin separates these species from the 

 genus Amphileptus, on account of their not 

 possessing a reticulated integument like those 

 of the latter, and their consequently under- 

 going diffluence. 



BIBL. Duj. Infus. p. 404. 



DILOPHOSPHORA,Desm. A genus of 

 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 



(fig. 180). Dilophosphora graminis. 



D.gramims,I)esm. s P res magnified soo diams. 

 = Sphceria Alopecuri, Fries. Found in 

 France ; does not appear to have been met 

 with in Britain. 



BIBL. Desmazieres,^ww. 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 Pandaridae. 



Char. Lamellar elytriform appendages 

 covering the thorax, only one pair. Three 

 first pairs of feet setiferous; the posterior 

 foliaceous and membranous. 



D. alata and D. Lamnce 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, 



