﻿44 3IR. E. S. COBBOLD ON TEILOBITES FEOil [Feb. I9IO, 



Protolenus morpheus, sp. nov. (PI. VII, fig. 7.) 



A distinct species, but closely allied to the one previously described, 

 appears to be indicated by a nearly complete head-shield [566] 

 and several fragments, from the same bed of rock. It differs prin- 

 cipally in the glabella, but there are minor points which combine 

 :to give a decidedly different aspect to the head-shield. 



Cranidium: Size. — Rather smaller than the average of Proto- 

 lenus latoucliei ; length = about 5 millimetres. 



General form. — Semi-elliptical, but less elongate than Pr. la- 

 toucliei; proportion of length to width = about 4 : 6. 



General convexity. — About!. 



Glabella. — Strongly convex; parallel - sided, with a well- 

 rounded extremity ; less distinctly marked off from the frontal 

 limb than in Pr. latoucliei, but having a similar greatest elevation 

 in the anterior and posterior lobes ; furrows deeply impressed at 

 the sides and continuous across, straight and not inclined backwards. 



Occipital furrow and ring. — Unknown. 



Axial furrow. — Distinct, but less wide than in Pr. latoucliei', 

 sinking deeply (almost to a pit) forward of the ocular ridge. 



Fixed cheek. — As in Pr. latoucliei, but rather more tumid. 



Ocular ridge. — Kather more strongly marked than in Pr. la- 

 toucliei, and giving, in conjunction with the swollen ('puffy') 

 cheeks, a somnolent expression to the head. 



Postero-lateral lim b. — Unknown. 



Frontal limb and facial suture. — Apparently similar to 

 Protolenus latoucliei. 



Marginal rim and eye-lobe. — Unknown. 



The test of this species has the same superficial characters 

 as that of Pr. latoucliei ; but possibly it was stronger, for, so 

 far as known, it is always in a better state of preservation. In 

 this respect it recalls the test of Jlicrodiscus comleyensis, sp. nov., 

 from the same bed of rock, notwithstanding that this latter is 

 punctate instead of tuberculous. 



Locality and horizon. — The same as those of Pr. latouchei. 



lam indebted to Mr. Lake for pointing out to me that these 

 ■species belong to Mr. Matthew's genus. They differ considerably 

 from his three described species ; the Comley forms seem to have 

 comparatively short eye-lobes, the free cheeks figured have a rela- 

 tively smaller area and a much longer spine, and the frontal limb 

 is more extended. 



Mohicana, gen. nov. 



Intimately associated with the specimens of Protolenus and Micro- 

 discus comleyensis, and apparently confined to the same 3-inch bed 

 of grey limestone, fragments of rather larger trilobites occur, having 

 characters very similar to those of Micmacca (?) plana, Matthew, 

 which species Mr. G. F. Matthew only referred provisionally x to his 

 genus. 



1 Tran?. N.Y. Acad. Sci. vol. xiv (1895) p. 143 & pi. xi, figs. 2 a-2b. 



