222 MR. HENFREY ON THE ELATERS OF TRICHIA. 



with a power of 1000 diameters and a good light I could not clearly define the termina- 

 tions of the fibres. 



My observations as to the tubular character of the elaters, were decisive even before 

 clearly defining the fibres, since I could obtain a transverse sectional view in certain 

 curved filaments, which gave a circular form ; the spiral structure was clearly distinguish- 

 able with a power of 250 diameters ; but, in order to count the fibres, it was necessary to 

 take out a few elaters and mount them in the thinnest possible film of Hquid, under very 

 thin glass, and apply a magnifying power of 1000 ; then the individual fibres could be 

 made out quite clearly enough to allow of their being drawn with the camera lucida. 

 . These elaters may be regarded as very good test objects for the defining power of the 

 higher object-glasses ; or, perhaps, — considering the confusing effect of the crossing curves 

 of the different parallel spiral fibres, — as test objects by which to measure the value of 

 observations on the more difficult tissues. If we take them in this light, it must follow 

 that either the microscopes or the observing powers of Schlciden and Schacht are im- 

 perfect, and since the latter certainly is not the case, the conclusion is that observations 

 on very highly magnified bodies made by these observers, must be received with great 

 caution until they provide themselves with better instruments. 



Postscript. 



Since the above was written I have received some information on the subject from the 

 Rev. Mr. Berkeley, who fully agrees with me as to the existence of spiral fibres. 

 Mr. Berkeley directed my attention to the fact that Schmidel (Icones Plantarum) had 

 pointed out the existence of this structure in 1762 ; thus many years before the younger 

 Hedwig. I may transcribe Mr. Berkeley's remarks on Schmidel's figure : — " Spiral fila- 

 ments do not exist in Arcyria pumicea, the species which Schmidel has in view in tab. 33 ; 

 but he has mixed up with it some Trichia, figured in figs. 4, 12, 13, 14, 15, 16 ; and a 

 careful examination, with a lens, of fig. 16, and a reference to the text will show that 

 Schmidel was perfectly aware of the structure." In the copy in the British Museum I 

 find the spiral fibre of fig. 16 quite clear, without magnifying the drawing. 



" Cribraria purpurea is represented at the lower part of the same plate : no spiral 

 filament, so far as I have observed, exists in this species, nor can I, on a re-examination 

 of the fungus this morning, find any such appearance as that represented by Schmidel at 

 fig. 8. It is possible however that he may have had one of the red TricMce intermixed 

 with his Clathrus stipitatus, for his description is too circumstantial to allow of a suppo- 

 sition that so correct an observer could make so palpable a mistake." Mr. Berkeley 

 inclosed a specimen of this fungus with the filaments, and I also find no spiral filament. 



" Schmidel did not detect the structure in the species figured at his tab. 24, if that is a 

 real Trichia." He here represents the filaments as moniliform (fig. 7). Mr. Berkeley 

 also reminded me of his own discovery of threads with a single spiral fibre in Batarrea 

 (Hooker's Journal of Botany, ii. tab. 22. fig. 1, 1843). 



Mr. Berkeley very truly says in his note, that Schacht' s own figures contradict his text. 

 He gives a spiral or screwed appearance with three threads, which could not possibly 

 result from the twisting of a flat band ; this could only present two threads formed by its 



