Dr.F. R. Coiuper Reed — The genus Homalonotus. 315 



sutures cut the lateral borders in front of the genal angles; the 

 paraglabellar areas are sunken and circumscribed. The pygidiuni 

 having the same ornamentation is No. 11282, figs. 7a-d, from the 

 same locality ; this has an interrupted median row of tubercles on 

 the axial rings, with a lateral row of rather larger ones on each side ; 

 there are only about half a dozen small tubercles, rather irregularly 

 disposed, on the lateral lobes. The head-shield represented in Salter's 

 figure 2 (No. 11277) has the shape of Schwarz's IT. hippocampus,^ 

 but is rather poorly preserved on the upper surface ; it is certainly 

 more elongated and triangular than No. 11276, though from the 

 same locality. The large head-shield (No. 11278) from Warm 

 Bokkeveld outlined by Salter in his fig. 3 is crushed and imperfect, 

 but the presence of a distinct large tubercle on each side of the 

 glabella on the faint basal lobes is sufficient to separate it. Perhaps 

 it belongs to Lake's H. querniis.- 



With regard to Salter's figured specimens, illustrated by his 

 figures 4, 5, 6, 8, avb can merely say here that none of them agree 

 with the types of JI. Jferscheli in ornamentation or characters, but 

 they suggest a comparison with Schwarz's species H. horridus^ 

 and S. agrestis} 



Salter included the European Devonian species H. armahis, 

 Eurm.,^ in his section Burmeisteria, but the anterior end of the head- 

 shield has never been fully described or figured, and so far as we 

 know the truncate edge of the middle-shield corresponds with the 

 almost straight course of the transverse commissure of the facial 

 sutures. In the allied K. rhenamis, Koch,^ the anterior edge is 

 slightly concave and the lateral angles project in front, so that 

 Giirich has chosen the name Bigonus for this group (see below). 



The thorax in all the South African forms ascribed to H. Herscheh 

 is obscurely trilobed, and the axis is very wide. The pygidium is 

 always triangular and produced behind into a point; the segmenta- 

 tion is more or less distinct and the joints are numerous. The 

 presence of spines on various parts of the body cannot be regarded as 

 of primary importance, in spite of Salter's opinion, and in the type- 

 specimens of H. Herscheli they are either inconspicuous or absent. 



Apparently it was mainly because of the presence of spines that 

 Salter included the species H. elongaUis, Salt., and H. pradoanus, 

 De Vern.,' in his list of members of Burmei&teria. But in both of 

 these the pygidium is rounded behind and not acuminate. The first 

 species, H. elongaUis, belongs to the same group as H Champ ernownei, 

 Woodw.,® from Devonshire, and a new species, H. hifurcatus, Eeed 

 MS., from the same locality, of which the description awaits 



•^ Schwarz, op. cit., p. 388, pi. ix, figs. 5a, b. 

 " Lake, op. cit., p. 216, pi. xxvii, fig. 1. 

 " Schwarz, op. cit., p. 385, pi. ix, figs. la-c. 

 ■* Ibid., p. 386, pi. ix, figs. 2a, h. 

 •' Koch, op. cit., p. 12, pi. i, figs. 1-6. 

 I Ibid., p. 32, pi. iii, figs. 1-6. 



'' De Verneuil, Bull. Soc. Geol. France, ser. II, vol. vii, p. 168, pi. iii, 

 figs. 4a, h, 1850. 



^ Woodward, Geol. Mag., Dec. II, Vol. VIII, p. 489, PI. XIII, 1881. 



