PROETUS. 23 



each side ; nearly square, bluntly angulated and rather broader behind, circular in 

 front ; separated from the border by a wide tumid area denned by two distinct 

 grooves, the innermost of which is continued as a deep groove to form the sides 

 of the glabella ; frontal (and possibly other) furrows indicated by slight scars ; neck- 

 furrow distinct, linear, bow-shaped, separating two lateral nodules ; neck-lobe very 

 long, arched, with flattened surface, replaced on the sides by the before-mentioned 

 nodules, inner layer with fine, close, transverse striae. Border very prominent, 

 rounded, concentrically striated, very convex in front. 



Size. — Length of head 12 mm., depth 7 mm. 



Localities. — Two species in my collection are from Lummaton ; one in the 

 Torquay Museum is probably from Wolborough. 



Remarks. — These small heads differ from those of the common Proetus of 

 Lummaton by being more convex than is usual with that species, and by having a 

 definite convex area in front of the glabella, so as to give in profile a step-like 

 appearance, similar to that seen in P. frontalis, 1 Barr., from which species, 

 however, it differs in its squarer glabella. In P. ungnloides* Barr., this area is 

 broader, and the lobe of the glabella much smaller; in P. complanatus, s Barr., the 

 latter is small and flat ; and in P. intermedins, i Barr., it is much smaller, and 

 the neck-lobe is narrower. In P. pictus, Giebel, 5 also the frontal area appears 

 larger and flatter, and the glabella more squared in front and with more oblique 

 sides ; F. A. Eomer's figure, 6 however, of that species, evidently incorrect, comes 

 nearer to it. In the present form the general shape of the glabella is the same as 

 that of the common Lummaton species, from which, however, Mr. Marr concurs 

 with me in regarding it as distinct. One of the specimens retains the cheeks, 

 but they are too indistinct for description. 



3. Peoetus Champernowni, n. sp. Plate II, figs. 13, 14. 



Description. — Pygidium small, convex, semicircular, smooth. Axis elevated, 

 very conical, about three-quarters of the length of the tail, bounded by a slight 

 groove, terminated steeply behind, and there followed by a slight swelling towards 

 the margin. Kings of the axis nine, decreasing rapidly, each bearing a distinct 

 central, and the first three or four indistinct lateral tubercles close to the groove. 



1 1852, Barr., 'Syst. Sil.,' vol. i, p. 440, pi. xv, figs. 10—14, Et. F. 



2 Ibid., p. 443, pi. xv, figs. 23—27, Et. F. 



3 Ibid., p. 463, pi. xvii, figs. 34—41, figs. 31—33, Et. E and F. 



4 Ibid., p. 464, pi. xvi, figs. 31—33, Et. E. 



5 1858, Giebel, Sil. Faun. Unterbarz., p. 6, pi. ii, fig. 7. 



6 1855, F. A. Eom., ' Beitr.,' pt. 3, pi. xvi, fig. 13. 

 4 



