150 BRITISH PALAZOZOIC FOSSILS. [Crusracea, 
Position and Locality.—Black shale of Builth, Radnorshire. 
Explanation of Figures.—P1\. 1. F. fig. 1. Natural size from the black shale of Builth.—Fig. 1 a. Two 
thoracic segments of ditto, magnified to shew the coincidence of their form and pleural furrow with Ogygia. 
Genus. LICHAS (Dal.) 
Gen. Char—Body ovate, very flat; surface granulated, head semicircular; glabella large, semioval, with 
one long segmental furrow curving inwards and downwards from the upper third of the glabella on each 
side, nearly to the neck-furrow, partially enclosing two large oval spaces, and close to the ends of the 
neck-furrow a posterior pair of furrows enclose a very small trigonal lobe on each side; neck-segment 
broader than the base of the glabella; cheeks small ; gyes moderately large, reniform; eye-line cutting the 
outer margin in front of the angles ; thorax of ten segments, plewrer flat, faleate, each with a fine slightly 
sigmoid pleural furrow, not reaching the margin; pygidiwm semi-oval, axis undefined, the lateral furrows 
instead of encircling the end, converge about the middle, and diverge again towards the posterior margin, 
which they do not reach, two short segments at the anterior convex part; side-lobe, flat, of two broad 
falcate ribs on each side projecting beyond the margin, each with a fine mesial duplicating groove; middle 
lobe semielliptical, pointed, a small divisional line coming off from the middle of the dorsal furrow on each 
side, curving downwards and outwards towards its’ extremity, so as partially to include an oval space on 
each side. 
LicHas PRoPINQUA? ( Bar.) 
ef —Barrande. Notice Prélimin. p. 54. 
Sp. Ch.—Pygidium semielliptical, obtusely pointed; axis semicylindrical, about one-third the entire 
length, of two narrow ring-shaped joints and a conical slightly longer portion, which becoming abruptly 
narrow and depressed is continued as an obscure ridge to the end; the three flat side-lobes each duplicate 
by a strong sulcus reaching almost the whole length, and slightly nearer the posterior than the anterior 
margin; the posterior pair of lobes anchylosed with the centre in one lozenge-shaped piece, the ends of the 
two upper pairs slightly project separately at the margin; swface covered with very unequal, sharp, conical 
granules, their own diameter apart. Length one inch two lines, width the same. 
The only doubt I have in referring this fossil to Barrande’s species, with which it agrees in form and 
peculiar granulation, is that he compares the form with the ZL. scabra (Bey.), without saying whether the 
extremity is notched, as in that species, or not. 
Position and Locality—Coniston limestone, Coniston Water-Head, Lancashire. 
Subgenus. ACANTHOPYGE (Haile and Corda). 
Gen. Char.—Cephalic shield semicircular, with the lateral angles produced backwards into small spines ; 
glabella large, moderately gibbous, narrow at the base, from whence nearly to the anterior margin the 
middle portion is nearly parallel-sided, defined by the retroflexion of the anterior pair of segmental furrows, 
which enclose on each side a large oval, very gibbous, space by their confluence behind with the lateral 
bounding furrow of the glabella; a little below this a posterior segmental furrow forms a simple transverse 
line, parallel with the neck-furrow and a little anterior to it, the enclosed space about equalling the neck- 
segment in size, often with a tubercle at each end; cheeks triangular, gibbous, having a small rounded eye- 
lobe near their upper and outer part, from which the eye-line runs directly upwards and inwards towards 
the glabella, and backwards and outwards to cut the external margin a little in front of the lateral angles ; 
surface granulated; pygidiwm semielliptical, the apex terminating in two long spines, axis suddenly attenuated 
posteriorly, of one joint, sides flat, each with two narrow prominent ribs, running out at the margin to 
long spines. 
