REMOPLEURIDES COliRECTUS. 15 



Remopleurides correctus, Reed. Plate II, fig-. 10. 



1903. Bemopleiirides correctus, Reel, op. cit., pt. i, p. 37, pi. vi, figs. 1 — 5. 



A fairly well preserved thorax attached to a glabella belonging to tliis species 

 extends our knowledge of this interesting member of the genus. The specimen 

 was obtained from Balclatchie, where the typical examples of the species are 

 found. The glabella has the rather longer tongue expanding anteriorly which the 

 variety from Dow Hill {op. cit., p. 38, pi. vi, figs. -1, 5) possesses, and near its front 

 end the reticulate ornamentation changes into somewhat regularly and widely spaced 

 concentric lines; in other respects the characters are typical. The thorax is elon- 

 gated and narrow, and possesses in this specimen 10 or 11 segments; the axis is 

 wider than the pleurfB, is moderately convex and tapers slowly ; the axial rings 

 are covered with small but not numerous tubercles, and on none of them is there 

 any sign of a median spine. The pleurse are falcate, with the fulcrum situated at 

 about one-third of their length, and it is only marked by a slight swelling of the 

 anterior edge and not by any definite projecting knob as in It. colhll and other 

 species, and the posterior margin is not notched. A broad oblique shallow furrow 

 traverses the surface of each pleura tapering to the tip, which is produced into a 

 slender recurved free point ; the under surface of each pleura is transversely 

 striated. The pleurae seem to be of uniform size, and there is no evidence that any 

 one of them was specially enlarged or elongated. The pygidium is not preserved. 

 The thorax measures 15 mm. in length and the axis is 5 mm. wide at its front end; 

 the glabella attached to it measures 7"5 mm. in length. 



The affinities of the thorax are with U. (Teratorhynchus) bicornis and also with 

 B. dorsospinifer ; in the simplicity of the pleurae it agrees with the former, and in 

 the proportions of axis and pleurse with the latter. 



In connection with this species it may be remarked that there seems to be 

 more than a superficial resemblance between the genera Bemopleurides and 

 Apatocpphalus ; the presence of a pre-glabellar area on the head-shield of the latter 

 and the absence of deflection in the tongue of its glabella seem to be the principal 

 points of distinction. The glabella, eyes and free-cheeks of such a species as Apato. 

 pecten, Wiman,^ show many features of similarity to B. correctus, R. barrandei, 

 B. bicornis and other species. There appears to be reason to believe that the 

 pre-glabellar area has only been much reduced in Bemopleurides. The peculiar 

 position of the genal spine is identical in A. pecten and E. bicornis. If we compare 

 A. serratus (Boeck), and A. schlotheinii (Billings), with the above-mentioned species 

 of Bemopleurides, we shall see further points of resemblance ; and even when we 

 look at the pygidium we can see how in the reduced number of axial segments in 



1 Wiraan, 'Arkivf. Zool.' (Stockholm), vol. ii, uo. 11 (1905), p. 6, pi. i, figs. 7-12. 



