1850.] FLETCHER ON DUDLEY TRILOBITES. 237 



the axis and sides, I am induced to regard PI. XXVII. fig. 7, as the 

 young of this species ; the connecting ridge, however, is shorter in 

 this specimen. The termination of the axis as represented in the 

 figure is too ohtuse. 



The young specimen last mentioned exhibits the incurved margin ; 

 it is very convex and strongly marked with concentric lines, which also 

 cross the spines. It has three lateral ribs on each side, but the 

 middle rib probably represents the tubercular interstice of the older 

 specimen. 



3. L. Grayii, n. sp. Pl. XXVII. fig. 8 ; and PI. XXVII. his, 



figs. 3, 3 «, & 3 6. 



The outline of the cephahc shield is nearly 'semicircular, but slightly 

 gibbous in front, and the surface granular, but not coarsely tubercu- 

 lated. Glabella very large and regularly convex, as broad in front as 

 behind. Forehead lobe continuous from the narrow front margin to 

 the neck lobe, and narrowing posteriorly, but expanding suddenly at 

 the base, where it has a slight prominence on each side. Its anterior 

 part is wider and more convex than the upper lateral lobes, which it 

 overhangs. Upper lateral lobes pointed, but rather obtusely below, 

 and not extending to the neck furrow. Lower lateral lobes triangular 

 in form, and smaller than the upper ; basal lobes small, narrow, ellip- 

 tical, and placed widely apart ; neck lobe broad, but not very promi- 

 nent. All the furrows which divide the lobes of the head are shallow. 

 Facial suture following the course of the anterior part of the glabella 

 as far as the eye, its posterior course being unknown. Wing trian- 

 gular and pointed, supporting the lunate eye upon a raised tubercular 

 base ; surface covered with tubercles of unequal size, and the incurved 

 front edge strongly and concentrically striated (PI. XXVII. bis, 

 figs. 3, 3«, 36). Eye moderate in size, and separated only by a slight 

 furrow, not by any portion of the cheek, from the lower lateral lobe 

 of the glabella. 



I have named this new species after my friend Mr. John Gray, of 

 Dudley, whose fine collection is well known to all admirers of Silu- 

 rian fossils. 



The head of this species has been figured in the * Memoirs of the 

 Geological Survey,' vol. ii. pt. 1. pl. 8, from a Malvern specimen, 

 which was too imperfect to name. 



4. L. Salteri, n. sp. Pl. XXVII. figs. 9 & 9 «; and Pl. XXVII. 



bis, fig. 4. 



Glabella regularly convex, and broader in front than at the base ; 

 forehead lobe linear, more convex than the upper lateral lobes, about 

 equal to them in width, not expanded below, but extending to the 

 neck lobe. Upper lateral lobes ovate in form, and pointed in their 

 lower portion ; lower lateral lobes slightly tumid ; cheeks (of which 

 I find only a small portion supporting the eye) moderate in size, and 

 separated from the glabella by a shallow groove. Eyes large and 

 convex, the eyelid (rather exaggerated in fig. 9 a) nearly the size of 



