OF THE GENUS TRICHIA. 17 



in T. chrysosjperma the peridia, although quite distinct, are 

 so densely aggregated as to cover completely the spot upon 

 which they are spread, in T. serimJa the peridia are flexuous, 

 creeping, and irregular in shape. When the fungus is mature 

 the peridium bursts, and the spores in its interior are dis- 

 charged. It is generally supposed that one purpose for which 

 the threads are designed is to assist in scattering the spores, 

 for their elasticity is very great. If a specimen of Trichia be 

 examined immediately after the bursting of the jyeridium, the 

 threads are seen protruding through the fissure and apparently 

 struggling for egress ; when viewed through the microscope 

 at this period with a low power, they have a slow waving 

 sort of motion, not unlike that of the threads of the Oscilla- 

 torice ; if the whole of the mass of threads be extracted with 

 a needle it appears like a small fragment of yellow wool. 

 When a minute portion of this yellow flocculent mass is ex- 

 amined moist, under the microscope, with a power of about 

 200 diameters, it is seen to consist of narrow delicate fibres 

 having fine spiral markings covering the whole of the walls. 

 A reference to fig. 1, Plate II., which shows a fibre of Trichia 

 chrysosperma, will give a general idea of this spiral appear- 

 ance ; and it is with regard to the nature of these threads, and 

 the cause of their spiral appearance, that so much difference of 

 opinion exists. Corda claims to have discovered these threads, 

 which he calls spiral-fibi'ous-cells {spiral-fiber- zellen) ; but they 

 were observed about tlie same time by Mr. Berkeley, and in 

 fact could not fail to have been noticed by any person hap- 

 pening to examine a fragment of the woolly mass with a 

 moderately good microscope.* 



Corda, in a letter addressed to Baron Humboldt, and which 

 was published at Prague in 1837, enters at some length into the 

 nature of these spinal-fibrous cells, and considers them to be 

 analogous to the elaters of the Jungermannige. After ad- 

 mitting that weighty objections might be raised against the 

 comparing of them with the spiral cells found in the walls of 

 the capsules of the Jungermanniae, and in the sporangia of 

 the Equisetacese, or with those in the leaves of Sj>hagnum, he 

 comes to the conclusion that no unprejudiced person can deny 

 the following facts with regard to their structure : — 



1. That they consist of a simple or stratified cellular mem- 

 brane. 



2. That this membrane encloses one or more spiral fibres. 



3. That the spiral fibre is of a rigid fibrous structure. 



He then traces the spiral form through the cells of 



* The structure seems to have been first noticed by Hedwig, Obs. Eot. 

 Fasc., i. p. 14 ; and next by Kunze, Myc. Heft II., p. 1)4. 



VOL. III. C 



