HARPES. 31 



Size of the Head. — 24 mm. in length from the border to the neck-lobe ; 39 mm. 

 from the border to the extremity of the cheek-spine; 24 mm. in width; 9 mm. 

 in depth. 



Localities. — There are four specimens from Lummaton in my collection ; 

 another (Phillips's figured specimen) in the Lee Collection in the British Museum ; 

 and two or three others in the Museum of the Torquay Natural History Society. 

 There is also a fine but defective specimen from Wolborough in the Museum of 

 Practical Geology at Jermyn Street. A imique and minute specimen of the tail is 

 in the Lee Collection in the British Museum. 



Remarks. — The cephalic shield of this beautiful Crustacean appears to agree 

 exactly with the German fossil as shown by comparison with Goldfuss's fine figure 

 and with a specimen from Germany in the British Museum. Burmeister supposed 

 it to be the same species as Harpes ungula, described by Count Sternberg in 1833 

 in the ' Transactions of the National Museum at Prague/ pp. 45, 52, pi. ii, fig. 1 ; 

 but Barrande's figures 1 of that Trilobite prove it to be specifically distinct. In that 

 fossil the border is more regularly rounded, the eyes are much farther apart, the 

 glabella is less prominent, the depth of the head is less, and the neck-furrow is 

 narrower. 



Barrande's Harpes venulosus' 2 more nearly approaches it, but differs, though in 

 a less degree, in the same particulars ; the eyes especially being much wider apart, 

 and the cheeks more elevated and wider ; the lobes of the glabella are also differently 

 arranged. H. reticulatus, Corda, 3 is the Bohemian species which is most similar 

 to it; but even from that there are several distinguishing features. Its eyes are 

 more anterior, the glabella more rounded, the neck-lobe more prominent, the lateral 

 lobes more defined, and the marginal area flatter all round, and especially at the 

 postero-lateral angles. Harpes transiens* is very indistinctly figured by Barrande. 

 It bears much resemblance to the present species, but appears distinguishable by 

 its greater width, more circular form, shorter glabella, and coarser ornamentation. 

 Harpes gracilis, 5 Sandberger, is a much flatter form presenting numerous diver- 

 gencies ; and Harpes Bischofii, F. A. Rom., both as given by Romer in his ' Beitrage ' 

 and by Kayser in the ' Abhandlungen zur Geol. Specialkarte von Preussen,' Band. 2, 

 pt. 4, is a species with a more cylindrical glabella and a very concave marginal area. 



Harpes convexus, 6 Trentk., is a very small species, differing in the strong border 



1 1852, Barr., ' Syst. Sil.,' p. 347, pi. viii, figs. 2—6, and pi. ix, figs. 1—6, Et. E. 



2 Ibid., p. 350, pi. viii, figs. 11—15, and pi. ix, figs. 11—19, Et. E and F. 



3 Ibid., p. 353, pi. ix, figs. 20—24, Et E. 



4 1872, Ibid., vol. i, Suppl., p, 7, pi. xv, fig. 40,41, fit. H. 



5 1850, Sandb., 'Verst. Khein. Nassau,' p. 28, pi. iii, fig. 1. 



c 1867, Trenkner, ' Pal. Novitat.,' p. 2, pi. i, fig. 1 ; and 1885, Clarke, ' Neues Jahrb.,' pt. 3, Beil.- 

 Band, p. 324, pi. iv, figs. 2,3. 

 5 



