58 Physiology of the Gyropodium coccineum 



of the cavity, but not attached to the sack containing it, 

 except at the upper part, around the mouth or opening 

 formed by the valves. This innermost sack is filled with 

 a white pulpy mass, which, as the fungus advances to ma- 

 turity, becomes a yellowish powder, very fine and light. 

 There can be no doubt but this constitutes the seed; and 

 the manner in which this is defended and discharged, is the 

 most striking peculiarity in the fungus. The interior sack, 

 containing this powder, or seed, although thin and tender, is 

 quite elastic, considerably resembling deer's leather. The. 

 valves open directly into this sack, and when the seed is ripe, 

 the sack gradually contracts, and thus forces open the valves 

 and sends forth the powder; the envelope immediately en- 

 closing it, not being compressed, or affected. This con- 

 traction of the inner sack, will, of course, produce a vacu- 

 um in the lower part of the outer one, or between the two, 

 and draw up that containing the powder towards the mouth: 

 for they are so firmly fastened together around the mouth 

 that no air can pass into the cavity between the sacks. E 

 is a vertical section of the head of the fungus, taken from a 

 specimen in which the inner sack had so much contracted, 

 that about half its contents were discharged. Whether the 

 vacuum between the sacks is filled with atmospheric air, 

 findingits way through some imperceptible interstice, or with 

 a gas generated by the processes going on in the plant, are 

 questions which I could not settle ; though disposed to 

 adopt the latter supposition. I am inclined also, to believe, 

 that the air which fills this cavity, exerts an influence in 

 forcing the contents of the inner sack through the valves. 

 For, in some specimens, in an advanced state, I observed 

 ihe inmost sack itself forced out of the mouth of the fun- 

 gus, so as to turn it inside ouhoards, as is represented at D. 

 And 1 can conceive of no way in which this could be ef- 

 fected, but by the pressure of the air beneath ; and as the 

 outermost of the two inner sacks is gelatinous, it contracts 

 when beginning to dry, and this would produce the effect 

 mentioned above of forcing out the inner sack. By a slight 

 and rather sudden pressure upon a specimen half exhaust- 

 ed of its powder, I have often seen the powder thrown out 

 in profusion to the distance of six or eight, and even 

 twelve inches, and then it floated in the air, having nearly 

 the same specific gravity. 



