532 Rev. G. F. Whidhorne — Devonian Fossils, Devonshire. 



Okthotetes hipponyx, Schnur, sp. (PL XVII, Fig. 8.) 



1878. Streptorhynclms Devonicus, Kayser: Abh. Geol. Specialk. Preuss., vol. ii, 



pt. 4, p. 199, pi. xxix, figs. 3, 4. 

 1897. Orthotetes hxpponyx, CEhlert : Biill. Soc. Geol. Fr., ser. iii, vol. xxiv, p. 856, 



pi. xxvii, figs. 9-11. 



Numerous specimens of a shell akin to 0. umbraculum come from 

 the " Cutting under Eailway N. of Barhrick Mil], Lynton." They 

 appear to belong to a widespread Lower Devonian species, to which 

 CEhlert, rejecting D'Orbigny's name Devonicus, has applied the one 

 which Schnur had first adopted, but afterwards dropped upon wrongly 

 identifying his shell with Vanuxem's. 



ffihlert gives various distinguishing characters which, even in the 

 imperfect condition of our shells, seem to hold good, except that ours 

 are not of so large a size. Our shells are remarkable for the very 

 great size and irregularity of the hinge-area of the ventral valve. 

 This sometimes appears triangular in shape and higher than its 

 length, and sometimes irregular in shape but still high. The rest 

 of the shell seems little affected by this contortion of the umbo. 

 The hinge-line, though sometimes auriculate, is not generally equal 

 to the greatest width of the valve. It seems also to differ from 

 0. umbraculum by being more circular, by the method of increase of 

 its ribs, by not being roughened by the existence of dense transverse 

 striations, and by other particulars. 



It is rather curious that this irregular shape and great size of the 

 hinge-area should be so pronounced in a Lower Devonian form, 

 when it does not appear in higher Devonian zones, but becomes 

 again exceedingly noticeable in Carboniferous varieties of 0. crenistrta, 

 as witness Davidson's plates. 



Our figure, unfortunately, does not show the distinguishing 

 characters of the shell, which I did not realize until after it had 

 been drawn. 



Coblenzien. 



Oethis longisulcata, Phillips. (PI. XVII, Fig. 9.) 

 1840. Orthis longisulcata, Phillips: Pal. Foss., p. 62, pi. xxvi, fig. 105. 



From the " Cutting under Railway N. of Barhrick Mill, Lynton," 

 and " Woodabay, above Pier," are several specimens of a rather large 

 Orthis. It has a transversely oval form, rather elevated umbo and 

 short hinge-line, and is covered with very fine divaricating striae, 

 which arch outwards on the shoulders. Its muscular area is large. 



This appears to be the species described by Phillips, though his 

 drawing is rather smaller. It was doubtfully united by Davidson to 

 0. arcuata, Ph., from Hope's Nose, from which, I think, it is really 

 quite distinct. It bears much resemblance to the shell figured by 

 Kayser and CEhlert as Orthis palliata, Barrande, but our shells 

 present no evidence of a double hinge-line. 



PhyiiLGpoka aspera, Ulrich ? 

 1890. Phyllopora aspera, Ulrich : Geol. Siirv. Illiu., vol. viii, p. 613, pi. xliv, fig. 5. 

 Specimens from the "Eoad Section above Watersmeet " and the 

 "Quarry in road above Crock Point, Woodabay," show little to 



