BUFFALO SOCIETY OF NATURAL SCIENCES 143 



and form a large angle with the axis. Outer half of the thin, wing side 

 of spine smooth, without ornamentation; on cutwater side ornamenta- 

 tion extends clear to the margin. 



Named for Prof. Clifton J. Sarle of St. Lawrence University, Canton, 

 N. Y., who collected this and other specimens now in the Buffalo 

 Museum. 



Remarks. — This species differs from the three other American 

 Devonic species known. It is closest to Gyracanthus primcBvus East- 

 man,^' from the Marcellus shale; which, however, besides being from 

 a lower horizon, differs in several important points. In G. sarlei, the 

 ornamentation extends clear to the cutwater margin, whereas in G. 

 primcBvus there is "a smooth and highly polished enamelled band, 

 adjacent to the front margin." On the other hand, conditions are 

 reversed as regards the ornamentation of the thin, wing margin; in 

 G. sarlei the outer half of this margin is smooth and unornamented, 

 whereas in G. primcevus it is ornamented up to the edge. In G. sarlei 

 moreover, the ornamental striae on the wing half of the spine are less 

 inclined to the axis, being only the kast bit off the true vertical, and 

 there are no headings or tuberculations on the striae adjacent to the 

 inserted portion as in G. primcevus. 



From Gyracanthus incurvus Traquair,^" from the Lower Devonic of 

 Campbelltown, N. B., G. sarlei is distinguished by differences in 

 ornamentation and other details. 



From G. sherwoodi Newberry, from the Chemung and Catskill of 

 New York and Pennsylvania, it is distinguished by its smaller size, 

 by tHe striae being much less inclined to the axis of the spine, and by 

 the absence of tubercles or beading from them. 



It is worthy of note that Gyracanthus sarlei has considerable resem- 

 blance to Machcer acanthus, and if not for the distinctive Gyracanthus 

 ornamentation, would be regarded as a species of this genus. Thus it 

 has a Machcer acanthus-like cross-section, and a smooth lateral wing, 

 which thins out to a knife edge, as in this genus. It has long been 

 known that Machcer acanthus has much resemblance to Acanthodian 

 spines; and the present specimen on the one hand, and MachcBra- 

 canthug sulcatus (which has an ornamentation of lines running parallel 

 with the axis of the spine) on the other, help to bridge the gap between 

 these two genera. 



53 Devonian fishes of Iowa, 114, and text-fig. 17, 1908. 



^ For a figure of this species see Woodward, A. S.: On the Lower Devonic fish fauna of Camp- 

 belltown, N. B. Geog. Mag., [3], viii, 1-6, pi. i. figs. 4-5, 1892. 



