MUCEDINES. 



[ 619 ] 



MUCEDINES. 



interesting of the microscopic fungi, noted 

 for their destructive influence upon organic 

 bodies which they attack. The species of 

 Botrytis, Oidium, &c. spread with won- 

 derful rapidity as mildews over the herba- 

 ceous parts of vegetables and moist vege- 

 table substances generally; in the former 

 situations their spores enter the stomata, 

 their mycelia ramifying among the subjacent 

 cells, and carrying decomposition and decay 

 into all the soft structures. They are most 

 abundantly developed in a close, damp at- 

 mosphere. The mycelia of other kinds, as 

 of PENICILLIUM, growing in liquids con- 

 taining organic matter, or upon decaying 

 vegetable substances, produce remarkable 

 chemical decompositions, causing a fer- 

 mentation of the medium in which they 

 exist. 

 See PENICILLIUM and FERMENTATION. 



Synopsis of British and nearly allied Genera. 



A. Fertile filaments (pedicels) simple or 

 branched, terminating in single spores or 

 a very short row. 



* Spores simple. 



Botrytis. Pedicels erect, septate, 

 branched ; branches and branchlets septate ; 

 spores solitary, on the tips of the branch- 

 lets, which are either racemose, umbellate, 

 cymose (Polyactis), paniculate, verticillate 

 (Acrostalagmus), spicate (Haplaria) or ca- 

 pitate. 



Peronospora. Like Botrytis, but the 

 pedicels without septa; often producing 

 resting-spores. 



Verticillium. Pedicels erect, septate, with 

 whorled branches terminating in a solitary 

 spore or a short row of spores. 



Acremonium. Pedicels short, subulate, 

 branches from a horizontal filament, bearing 

 single smooth spores. 



Zyyodesmus. Like the last, but with 

 echinulate spores. 



Oidium. Pedicels simple, short, erect, 

 clavate, septate, bearing usually one, some- 

 times two more or less oval spores. 



Fasidium. Pedicels very short, pulvinate. 

 Spores elongate, fusiform. 



Menispora. Pedicels erect, septate, bear- 

 ing fusiform or cylindrical spores, at first 

 joined in bundles. 



Sceptromyces. Pedicels erect, geniculate, 

 verticillately branched ; branches short, race- 

 mose ; spores in grape-like bunches. 



** Spores septate. 



Brachycladium. Pedicels branched above, 

 septate, moniliform; branches and branchlets 

 forming a sporiferous capitulum; spores 

 transversely septate. 



Trichothecium. Pedicels interwoven in 

 tufts, the central erect, fertile ; spores acro- 

 genous, didymous, free, commonly loosely 

 heaped together. 



Cephalothecium. Pedicels simple, con- 

 tinuous, bearing a terminal head of didymous 

 spores. 



B. Erect filaments (pedicels) terminating in 

 strings of spores. 



* Spores simple. 



Penicillium. Pedicels erect, septate, peni- 

 cillately branched above ; branches and 

 branchlets septate ; strings of spores attached 

 to the tips of the branches. 



Sporotrichum. Pedicels erect, simple or 

 slightly branched, septate and articulate, 

 articulations remote, inflated ; spores simple, 

 usually found collected in heaps among the 

 filaments. 



Briarea. Pedicels erect, septate, with 

 terminal moniliform chains of spores, 

 crowded into a head. 



Gonatorrhodon. Pedicels erect, septate, 

 with chains of spores in a terminal head 

 and in whorls at the joints. 



** Spores septate. 



Dendryphium. Pedicels erect, septate, 

 unbranched ; strings of spores attached in a 

 bunch to the apex ; spores septate. 



Dactylium. Pedicels erect, septate, 

 branched above; strings of septate spores 

 attached singly or in pairs to the apices of 

 the branches. 



C. Fertile filaments (pedicels} inflated at 

 the tips or at various points in their 

 length, with projecting points or warts 

 on the inflations, bearing 



* Simple spores. 



Aspergillus. Pedicels continuous, erect, 

 simple filaments, inflated into a little head 

 at the summit ; bearing moniliform chains of 

 spores, crowded into a capitulum. 



Rhinotrichum. Pedicels erect, septate, 

 sometimes sparingly branched, the apices 

 clavate, cellular, bearing scattered points 

 supporting simple spores. 



