DELTOMONAS. 



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DEMATIEI. 



cately membranous. Fructification double ; 



1. Conceptades (coccidia) external, or half- 

 immersed, hemispherical, usually imperfo- 

 rate, containing beneath a membranous peri- 

 carp a tuft of dichotomous filaments, whose 

 articulations are finally changed into spores. 



2. Tetraspores in distinctly definite son, 

 either scattered through the frond or placed 

 in proper fruit-lobes or sporophylls. 



Synopsis of British Genera. 



Delesseria. Frond leafy, of indefinite 

 form, with a percurrent midrib. 



Nitophyllum. Frond leafy, of definite form, 

 without a midrib (sometimes traversed by 

 vague, vanishing nerves). 



Plocamium. Frond linear or filiform, 

 compressed, much branched, distichous; 

 ramuli pectinate, secund. 



BIBL. See the genera. 



DELTO'MONAS, Kent. A genus of 

 Flagellate Infusoria. 



Char. Bodies variable, wedge-shaped, 

 stalked; flagella two, equal. Freshwater. 

 Multiplication by longitudinal and trans- 

 verse division, and the breaking up of the 

 body into germs. In ponds. (Kent, In/". 283.) 



DEMATIE'L A family of Hyphomy- 

 cetous Fungi, growing on the dead parts of 

 plants, and characterized by the mostly 

 septate spores being attached to rigid thick- 

 walled filaments, which are continuous or 

 septate. 



According to the observations of Tulasne, 

 many of the supposed genera of this family 

 are merely conidiiferous states of Ascomy- 

 cetous Fungi; for instance Cladosporium. 

 We enumerate them here according to the 

 older arrangement, as their history is not 

 yet fully cleared up. 



Synopsis of British Genera. 



Cephalotrichum. Fertile filaments stalk- 

 like, erect, septate, terminating in a globose 

 capitule formed by radiating forked or 

 ternate branches bearing globular spores 

 at their tips. 



Sporocybe. Filaments rather fibrous, 

 subulate, capitate, bearing simple spores 

 conglobated into a terminal head. 



GEdemium. Filaments rigid, erect, al- 

 most continuous, or annulated, bearing at 

 the sides globular masses of spores. 



Myxotrichum. Filaments erect, scarcely 

 septate ; fertile branches crowned by globules 

 of heterogeneous conglutinate spores. 



Helminthosporium. Filaments erect, 

 simple, septate ; spores transversely septate. 



Bolacotricha. Filaments simple, uni- 

 formly articulate at the apex ; spores con- 

 glomerated, large, globular, shortly stalked, 

 contents distinctly granular. 



Triposporium. Filaments erect, sep- 

 tate, sterile branches solitary, more or less 

 spreading ; fertile branches shorter, bearing 

 at the tips solitary, stellate, mostly very 

 shortly stalked spores. 



Helicosporium. Filaments erect, subu- 

 late, closely septate, continuous and dia- 

 phanous at the summit ; spores thread-like, 

 septate, spirally coiled, then expanding 

 themselves with elasticity. 



Cladotrichum. Filaments erect, septate, 

 branched ; branches and branchlets bearing 

 septate spores at their tips. 



Dematium. Filaments erect, septate, 

 with verticillate branchlets below, simple 

 and whip-like above ; spores crowded on the 

 apices of the ramules. 



Cladosporium. Filaments erect, septate 

 above, bearing the spores arranged in rows 

 forming short moniliform branchlets. 



Macrosporium. Filaments suberect, sep- 

 tate, delicate, evanescent, bearing erect, 

 stipitate spores, with many transverse and 

 usually some longitudinal septa. 



Arthrinium. Filaments tufted, suberect, 

 annulate, with opaque thickish septa; 

 spores fusiform, septate, large. 



Camptoum. Filaments as in the pre- 

 ceding ; spores ovate, curved, small. 



Arthrobotryum. Common stem com- 

 posed of jointed filaments. Spores large, 

 radiating, so as to form a little head, dark, 

 septate. 



Dendryphium. Filaments free, jointed, 

 simple below, branched above ; branches 

 and branchlets often monilioid ; spores sep- 

 tate, acrogenous, concatenated. 



Periconia. Stem composed of fasci- 

 culated compacted filaments ; head globose ; 

 spores fixed to the free tips of the fila- 

 ments. 



Haplographiwn. Filaments jointed, free, 

 black ; spores concatenate, hyaline. 



Monotospora. Filaments free, black, 

 bearing one or rarely two (by division) 

 large, black, subglobose spores at their 

 tips. 



Helicoma. Filaments erect, dark, jointed, 

 bearing on their sides pale, flat, spiral 

 spores. 



Polythrincium, Filaments moniliform; 

 spores springing from the midst of the fila- 

 ments, didymous. 



Gonatosporittm. Filaments erect, jointed, 



