HYPNUM. 



[ 408 ] 



HYPOG^EI. 



double, single, or absent, the internal or the 

 external or both bem? occasionally obsolete. 

 External : sixteen equidistant or more or 

 less geminate teeth, lanceolate, trabeculate, 

 with a longitudinal line, composed of a 

 double layer, arising below the orifice, 

 sometimes split into several irregular arms. 

 Internal : similar to the above, or capillary, 

 placed on a more or less exserted mem- 

 brane, conjoined by transverse appendages, 

 very often wholly or partly cancellate. No 

 interposed cilia. 



Pilotrichum. Calyptra mitriform. Pe- 

 ristome, &c. as in NECKERA. 



b. Internal peristome with interposed cilia. 



Hookeria. Calyptra mitriform. Peri- 

 stome double ; external teeth lanceolate- 

 subulate, with a more or less broad longi- 

 tudinal median line, trabeculate ; internal 

 on a more or less deep keeled membrane, 

 subulate, scarcely ciliiform ; rudimentary 

 cilia interposed, hardly conspicuous, or, 

 more rarely, perfect. 



Hypmim. Calyptra dimidiate. Peri- 

 stome double. External teeth sixteen, lan- 

 ceolate, trabeculate, with a more or less 

 broad longitudinal line, more rarely a fis- 

 sure, with more or less crest-like prominent 

 trabeculse within. Internal teeth on a 

 grooved reticulated projecting membrane, 

 lanceolate, articulated, grooved, solid or 

 perforated in the middle, or altogether 

 gaping and separating. Cilia one to four, 

 interposed, very often rudimentary. 



HYP'NUM, Dill. A large genus of 

 Hypnoideae (Pleurocarpous Mosses), here 

 including the species referred by modern 

 writers to Isothecium, Climacium, Leskea, 

 &c. Many of them are extremely common 

 in all woods, growing on trunks of trees, 

 banks, &c. ; others grow in water or in bogs, 

 &c. The distinctions of the species are 

 taken in great part from the forms &c. of 

 the leaves, which require the use of a 

 microscope for their accurate determination. 



BIBL. Wilson, Bryol. Er. 335 ; Hooker, 

 Br. Flora, vol. ii. pt. 1 ; Miiller, Syn. Mus- 

 corum. 



HYPO'CREA, Fr. A genus of Sphse- 

 riacei (Ascomycetous Fungi), with a hori- 

 zontal, sessile, or indistinct fleshy, mostly 

 coloured stroma, filiform asci, and simple 

 spores. The species of this genus, like 

 those of Hypoxylon, as given by Fries, are 

 partly referred to Sphceria by other authors ; 

 the distinctions will be best explained by 

 taking all these genera under SPHJERIA. 



HYPO'DERAS, Frauenfeld. A genus 

 of Acarea (Acarina). Numerous species, 

 occurring beneath the skin of birds, often 

 forming little cysts. Giebel, Verh. zool.- 

 bot. Gesell. Wien, xiv. 385; Murray, EC. 

 Ent. 228 (figs.); Robertson, Jn. Mic. Soc. 

 vi. 201. 



HYPODER'RLS, R, Brown. A genus 



Fig. 351. 



Hypoderris Brownii. 



Sorus with fringed indusium. 



Magnified 25 diameters. 



of Dicksoniese (Polypodiaceous Ferns), 

 with very prettily fringed indusia. Exotic. 

 (Hooker, Syn. 46.) 

 HYPOG^E'L A family of Gasteromy- 



Fig. 352. 



Hydnangium candidum. 



Basidiospores upon the hymenium. 



Magnified 400 diameters. 



Fig. 353. 



Hysterangium clathroides. 



Section of hymenium with oval basidiospores. 



Magnified 400 diameters. 



cetous Fungi, characterized by their resem- 

 blance to the Truffles (Ascomycetes) in 



