CONTRIBUTIONS TO PALiEONTOLOGT. 87 



The Genus Uphant^nia may be characterized as follows : 

 GENUS pPHANT^NIA ( Vanuxem). 



Circular or flabellate fronds composed of ligulate radiating and 

 concentric bands, the reticulations being produced by the sub- 

 stance of the frond J and not caused by superficial striae. 

 The entire form is unknown. 



The only species known is the Uphantcenia chemungensis of Yanuxem. 



For the obconical or subcylindrical stems, with or without flabel- 

 late fronds, I propose the name Dictyophyton, from the cancellate 

 surface of all the known species. 



GENUS DICTYOPHYTON ( n. g.). 



Flabellate or infundibuliform fronds with reversed conical or cy- 

 lindrical hollow stems, marked externally by cross strise which 

 divide the surface into minute rectangular spaces. 

 In many species there are two sets of striae, a coarser and more 



distinct set, with finer intermediate ones. Stems usually a little 



spreading at their bases, sometimes contracting above, and then 



spreading in flabellate or funnelshaped fronds. 



Types : Dictyophyton neiuberryi, D. filitextile & D. redfieldi. 



In some of the species, the surfaces of the stems are angular ; others are ~ 

 nodose or annulated. The casts of the interior present a similar striated 

 surface with the exterior.* ft 



DICTYOPHYTON NEWBERRYI ( n. s.). 



plate IV. FIGS. 1, 2 & 3. 



Stem subconical, apparently fibrous below, gradually enlarging above 

 and expanding into abroad spreading funnelshaped frond. Surface 

 marked by strong radiating and concentric strise, which divide 

 the surface into rectangular spaces, and between these are finer 

 sets of strise which cancellate the spaces between the coarser ones. 



In several specimens before me, this species does not exceed a height of 

 four or five inches ; while the diameter of the frond, when fully extended, 

 would be nearly as great. Numerous stems and fragments of stems, pos- 

 sessing the same general features, indicate the existence of fronds several -^ 

 times larger than the one figured. 



• Notwithstanding the objectionable name Hydnoceras, I would not have proposed 

 to change it, but to restrict its application to such forms as the original, which would j) 

 include D. ( H.) tuberosum and D. ( H.) nodosum; while Dictyophyton might have 

 included the other forms. But at the request of Mr. Conrad, I have dropped the use of 

 the term Hydnoceras, and have extended the definition of Dictyophyton to include 

 those forms. " / A , 



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