1862.] DAWSON DEVONIAN PLANTS. 323 



59. Rhachiopteris pinnata. Gen. et sp. nov. PI. XVI. fig. 60. 



Stipes half an inch wide or less, unevenly striate, giving off opposite 

 branches, which are abruptly broken off at short distances from the 

 stipe. 



Unger has established as a provisional family, under the name of 

 Bhachiopterides, a number of species, referred to several genera, of 

 stipes of ferns showing structure ; and I now propose under the 

 above name to include such Devonian stipes as indicate the existence 

 of distinct species of Ferns, of which the fronds have perished. This 

 has the advantage of provisionally recognizing the existence of such 

 species, and of preventing their stipes from being referred, in their 

 flattened state, to other families of plants. It also serves to remind 

 us of the fact that, while in some localities we have a number of spe- 

 cies of Perns in a good state of preservation, in others an equal number 

 of species are represented only by fragments of stipes. The latter 

 state of things is especially noteworthy in the Middle Devonian of 

 New York, from the lower member of which, the Marcellus Shale, 

 the present species is derived. 



60. Rhachiopteris cyclopteroides, sp. nov. 



Yery thick stipes, not observed to branch, and marked with uneven 

 longitudinal sti'ice. 



Base of the Catskill group, N"ew York. 



61. Rhachiopteris punctata, sp. nov. PL XVI. fig. 61. 



Stipes marked with obscure longitudinal ridges, between which are 

 transverse furrows or punctures ; greatest diameter an inch. 



These stipes are marked in the manner of those of Cyclopteris 

 Mimeriana, Goeppert, of the Upper Devonian ; and Unger figures a 

 similar stem from the Devonian of Thuringia. The present speci- 

 mens are from the Catskill group of ISTew York. Fragments with 

 similar markings occur both at St. John and Gaspe. 



62. Rhachiopteris striata, sp. nov. 



Stipes regularly and distinctly striated longitudinally. 



Many short fragments of these stipes occur on the surfaces of beds 

 of the Chemung group at Richfield, Ohio, and the Hamilton group at 

 Akron, Ohio. They are not distinguishable from similar fragments 

 of the stipes of Cyclopteris Acadica, and, like these, might, when 

 flattened, be mistaken for leaves with parallel veins. 



63. Rhachiopteris tenuistriata, sp. nov. PI. XIV. fig. S2a,b; and 



PI. XVI. figs. 45, 46. 

 Stipes smooth, finely striated, and in some specimens with little linear 

 ridges scattered over the surfaces, and perhaps marking the position 

 of minute hairs. Largest stems an inch in diameter, branching 

 pinnately and dichotomousl/y , and terminating in recurved divisions 

 or in long flattened petioles. 



More than one species may possibly be included under this name ; 

 VOL. xvin. — part i. z 



