38 Erwin Hinckley Barhour 



are perfectly fossilized, are hollow and free from filling of 

 silica, and their cellular structure faultlessly preserved. 



The amount of this gelatinous silica seems to be inversely 

 proportional to the perfection of preservation and fossilization. 

 Its presence is probably due to the efPects of organic decompo- 

 sition of the vegetable tubes rather than to the animal excreta 

 which some have proposed in explanation. 



As may be seen in Plate XII., Figs. 1 and 2, the great tubes 

 branch and wind about indefinitely throughout the interior of 

 the rhizome. They are pure white, hard, and flinty. The sur- 

 face is wrinkled, not unlike the bark of a vine, and is divided 

 into fairly distinct joints by certain nodular prominences. 

 The wall of such tubes is but a millimeter or two in thickness. 



Microscopic sections from these tubes reveal a cellular 

 structure so unmistakable, so defined and clean cut, as to be 

 equalled only by a section from a living plant. (Plate XII., 

 Figs. 4 and 5.) The tubes seem to branch repeatedly and to 

 grow smaller. In order to study them it is necessary to cut 

 away the rest of the Devil's Corkscrew, and some fine speci- 

 mens must be sacrificed in their behalf. 



Our present collection representing these perfectly preserved 

 tubes comprises three large and two small specimens. Their 

 study has been too recently begun to admit of exact descrip- 

 tion in this paper. However, this much is known: that they 

 are vegetable; that they are cellular, and not vascular; that 

 the body of the rhizome is occupied by them; all of which 

 imposes additional burdens and taxes on the ingenuity of that 

 long-suffering gopher which dug the burrow. 



MICROSCOPIC STRUCTURE. 



In studying the minuter structure of Daemonelix, many 

 difficulties are to be overcome. The fossil and matrix are 

 so soft and friable that sections can be cut only after the spec- 

 imens have been thoroughly imbedded and filled interstitially 



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