HYMENOniYLLUM. 



[ 406 ] 



IIYPIIOMYCETES. 



fissures between the teeth of the leaf, with 

 a truncated entire mouth ; annulus incom- 

 rlete. 



HYMENOPHYL'LUM, Smith.— Filmy 

 Ferns. The tj'pical genus of Hymenophyl- 

 laceous Ferns, remarkable for their delicate 

 structure and often almost moss-like habit. 

 Two dwarf species are natives of Britain, 

 H. tunhrkhjense and H. Wilsoni. Numerous 

 tropical species (Hooker, Syn. 50). 



HYMENOP'TEPtA.— An order of In- 

 sects, containing the Bees, &c. 



IIYPERAM'MINA, Brady.— A tubular 

 and sandy Foramiuifer, irregular in exten- 

 sion and growth. (Brady, Ann. N. H. 1878, 

 i. 433 ; Mic. Jn. n. s. xix. 13.) 



HYPERICUM, Linn. — Hinds points 

 out in the leaves of //. Androsa'inum, the 

 common Tutsan, and calijcinum, certain 

 dots containing active motile bodies {M. 

 M. Jn. xix. 2:!3). 



HYPEROMYX'A, Corda, See Cheiro- 



SPORA. 



HYPH'EOTHBIX, Kiitz.— A genus of 

 OsciLLATORiACE^ (Confervoid Algae). 



Char. Fil. simple, jointed, coloured, more 

 or less distinctly sheathed, tranquil ; fasci- 

 culate or densely united into a more or less 

 membranous non-radiate stratum (PL 52. 



58 European species. In sprnigs, coating 

 "water-plants in pools ; on rocks, &c. 



BiBL. Rabenhorst, Fl. Alg. ii. 75. 



HYPHOMYCE'TES. — A section of 

 Fungi composed of microscopic plants, 

 growing as moulds over dead or living 

 organic substances. These are now con- 

 sidered to be conidiiferous conditions of 

 Ascomycetous Fungi ; but as they are in- 

 teresting and often very beautiful micro- 

 scopic objects, the original account is re- 

 tained here. The vegetative structure or 

 mycelium creeps over or among the struc- 

 tures infested as a collection of delicate, 

 simple or branched, continuous or septate 

 filamentous cells {flocci), and produces the 

 spores either on lateral pedicels (from which 

 they soon fall off, becoming intermingled 

 with the mycelium), or in heads at the 

 swollen or ramified extremities of usually 

 erect filaments (figs. 344, 345, .340, and 347). 

 These filamentous pedicels in most cases 

 exhibit a contraction just below the point 

 of origin of the spore, giving theni_ the 

 same appearance as the pedicels of basidio- 

 Bpores. The spores are round (PI. 20. fig. 

 15), oval (fig. ;}47 and PI. 20. figs. 5, 0), 

 spindle-shaped (Fusisi'ORiuii), spiral (He- 



Fig. .344. 



Fi?. 345. 



Fig. 344. Cephalotheeimn roseum. Magn. 200 diams. 

 Pig. 345. Vex'ticillium nutans. Magn. 2uO diams. 



licosporitjm), and isolated or connected 

 (tig. 340) in beaded lines (Pemcillium, 

 Aspergillus), or grouped in a stellate 



Fig. 346. 



Btysanus Ciiput-Meduaae. 

 Maguifled liUO diamtters. 



form. In the Isariacei and Stilbacei the 

 erect pedicels are composed of a number of 

 conjoined filaments ; in the other families 

 the pedicels are simple filaments. Some 

 authors include among these plants the 

 Mucorini (Phycomycetes), regarding the 

 vesicular envelope of the spores there as a 

 mere veil, not a true cell producing the 

 spores in its interior. This fiimily is of 

 especifil interest from containing so many 

 moulds and mildews, and various parasi- 

 tical Fungi to which the' diseases of plants, 

 and in some cases of animals, have been 

 attributed. Further particulars respecting 



