Walter A. Bell

“ A feature carefully noted by Ulrich, and confirmed by the writer for the Kelly's Island species, is the presence not of a thick single wall as interpreted by Williamson, Dawson, and Knowlton, but of two thin walls with a broad intervening space, the inner spherical cavity communicating with the exterior by tubular prolongations of the inner wall at each end. The spiral ridges are restricted to the outer wall, and are a part or ornamentation of the wall itself, so that they afford no evidence of a Chara construction in support of the superficial appearance. ”

“ Although the general contour of the body and of the large cephalic shield resembles other Xiphosurians there is no apparent trilobation of the body and the presence of a distinct post-cephalic shield is unique. Were it not for the presence of the double shield and the absence of trilobation Schistaspis would be very similar to Belinurus, which has an abdomen of eight segments, of which the 7th and 8th are consolidated, in addition to a long, slender telson. Euproöps has seven abdominal segments fused together, besides a short caudal spine. ”

“ The lateral margins are bordered by a depressed band which broadens towards the antero-lateral corners. Anteriorly a distinct V-shaped cervical furrow joins the two flat marginal bands and divides the carapace into two unequally sized areas. The anterior of these areas has three distinct spine-bearing ridges, a median one forming the base of the rostrum, which runs for half the distance to the cervical fold, and a pair of lateral ridges on either side, which are directed so as to converge when produced at a point near the forward end of the rostrum. ”

“ Industrial exploitation of the long buried debris of these ancient forests for their use as fuel, has been the chief aid in satisfying our curiosity about the relationships and habits of numerous individual members of the Coal Measures plant and animal societies. ”

“ Whereas all the specimens from Kelly's island examined by the writer, and apparently those by Knowlton from the Falls of Ohio, have a right handed spiral twist to the ridges, Ulrich figures one with a left handed twist. Only nine spirals were observed by the writer in the Devonian specimens to which he had access. But the number of spirals, as evident from the discovery of Palaeochara, does not mitigate against a possible Characeous affinity of this fossil. A much more serious objection may be raised. ”

“ Genal angles produced into short bluntly acute spines. Between the prominent reniform compound eyes there is a pair of elongate elevations which border a median depression in which lies a circular ocellar mound 1.3 mm. in diameter. This mound is situated directly in front of a line tangential to the posterior borders of the eyes and was apparently the seat of the ocelli. A second pair of elevations run obliquely from the middle of the posterior border towards the lateral margins, so that the eyes are situated in triangular, depressed areas of the test. ”

“ Abdominal free segments 8 (?) in number, non-trilobate, with spine-like posteriorly directed epimeral projections. The first seven abdominal segments are single. The last abdominal segment is anchylosed to a small hemispherical tail plate which doubtfully bore a telson spine in articulation with it.
Schistaspis bretonenis n. sp.
Description: Length, exclusive of possible telson spine, 27 mm.; maximum width 12.6 mm. Cephalic shield large, with hemispherical outer border, and concave, evenly curved posterior border. Genal angles acute but scarcely prolonged into a spine. ”

“ Palaeochara n. g.—Oogonium like Chara, but with six, instead of five spirally wound investing cells. Genotype Palaeochara acadica.
Palaeochara acadica n. sp.
Description: Oogonium subglobular to pear-shaped with hemispherical base and conical apex. Length somewhat exceeding the greatest diameter. Investing cells six in number, commencing around a smooth, circular, basal area and making one cpmplete spiral turn to the raised conical end. Six or seven spiral ridges visible on a side view. Length 0.55 mm.; diameter 0.53 mm.; diameter of smooth basal area 0.075 mm. ”

“ These ridges abut on the cervical furrow but do not quite reach the anterior margin. The area behind the cervical furrow is marked by a very faint median keel which dies out entirely half a millimetre from the posterior border.
The surface viewed through a lens is roughly pitted, and the bases of larger spines lie on the rostrum and keels.
Dimensions: Extreme length 20 mm.; length, excluding rostrum, along median line, 13 mm.; length of rostrum projecting beyond anterior margin 5 mm.; width of rostrum at anterior margin 0.8 mm.; greatest width of carapace 17 mm. ”