210 MR F. R. COWPER REED ON 



Hyolithes sylvestris, sp. nov. (PI. II. figs. 9, 9a.) 



Shell short, straight, broad, tapering at about I in 2^. Ventral face unknown. 

 Dorsal face weakly convex, with narrow raised border, separated by broad shallow 

 groove ; surface ornamented with 30-40 fine, straight, thread-like longitudinal lines, of 

 equal size and at equal distances apart, crossed by very delicate, closely placed, arched 

 transverse strise. Dorsal lip strongly arched. 



Dimensions : — 



Length ........ 12'5 mm. 



Width at mouth . . . . . . .5-0,, 



Horizon and Locality. — Saugh Hill Group, Woodland Point. 



Remarks. — In shape this species, of which there is only one specimen, is indis- 

 tinguishable from H. penkillensis, but the ornamentation of the dorsal face is sufficient 

 to separate it. The shell is shorter than H crispatus (Boll. ),* but the ornamentation 

 somewhat recalls it, though the Swedish form shows no raised border. 



Barrande's H. columnaris,i from Stages E and F, has a concave dorsal face, but a 

 similar ornamentation. 



Perhaps Salter's Hyolithes anceps,\ from the Silurian of Eastnor Castle, is allied ; 

 the shape and ornamentation appear to be similar, but the species is imperfectly known, 

 and the type-specimen is indifferently preserved. 



Hyolithes, sp. ind. (a). 



An imperfectly known species of Hyolithes, somewhat resembling in shape 

 H. immemor, is represented by four specimens from Penkill, in the Hunterian Museum. 

 It is too poorly preserved to warrant giving it a specific name, but it is probably distinct 

 and new. The shell tapers at about 1 in 4 ; the dorsal face is slightly convex and has a 

 very slightly arched lip ; its surface is crossed by transverse strise ; there seems to be 

 no border nor marginal longitudinal lines, as occasionally seen in H. immemor. The 

 lateral angles appear to be sharp and acute. The ventral face is angulated or subangu- 

 lated, and marked with a few longitudinal lines, apparently about 1 2 or rather more in 

 number. 



One specimen measures 15 mm. in length, with an apertural width of about 4 mm., 

 and another about 12*0 mm. in length, with an apertural width of about 3 25 mm. 



Hyolithes, sp. ind. (/3). 



Some imperfectly preserved examples of an indeterminable species of Hyolithes 

 occur in the Mulloch Hill Group of Mulloch Hill. They are rather short, and taper 



* Holm, op. cit., p. 89, t. iii. figs. 36-52. 



t Barrande, op. cit., p. 78, pi. ix. fig. 13, pi. xii. fig3. 13-23. 



I Salter, Mem. Geol. Surv., vol. ii. pt. i., 1848, p. 355, pi. xiv. fig. 1. 



