158 BRITISH PALALOZOIC FOSSILS. [CrusTAcEA. 
few small irregular tubercles: pygidium much curved downwards, obtusely pointed, sides straight, nearly 
vertical; axis with about nine to eleven distinct segments, each of those near the end, and every alternate 
one above, with a strong tubercle at the middle, and all having one at each end; sides with seven or eight 
rounded ribs, having a tubercle at their origin, their ends blunt and prominent, and a few tubercles between. 
Length one inch three lines, width ten lines. 
I have not ascertained whether the ends of the posterior pleurze are prolonged in this species; they 
are all marked with obscure tubercles.—The distinction in character between the thoracic and pygidial seg- 
ments is not marked in the figure in the Sil. System, giving the appearance of too many body-segments. (They 
are only eleven). Brongniart’s figure, t. 1. f. 3. A. though agreeing closely in many respects with the other 
specimen, seems to differ in the great number of lateral segments to the axis of the pygidium, (so also Mr Curtis’ 
original figure, apparently of the same specimen in Buckland Bridg. Treatise, t. 46. f. 6, under the name 
Asaphus tuberculatus) ; and finally Mr Fletcher has just published figures of exactly similar specimens in the 
Quarterly Geol. Journal of London, Vol. VI. t. 32. (under the name Cybele punctata), which clearly prove 
the species to be a good one of the genus Hncrinurus by its eye-line and cephalic angles, and easily dis- 
tinguishable from the true #. punctatus by the narrow, tuberculated body segments, &e. 
Position and Locality.—Not uncommon in the Wenlock limestone of Dudley. 
Genus. ENCRINURUS. (Emmerich). 
Gen. Char.—Elongate ovate; cephalic shield semielliptical, tuberculated, the lateral angles produced 
backwards into spines; glabella pear-shaped, with three slightly-indicated segmental furrows at each side of 
the contracted base; cheeks flattened, triangular; eyes in the middle of the cheeks, elevated on tall footstalks ; 
eye-line extending from behind the eye direct to the outer margin, which it cuts in front of the angles; eleven 
body-rings shaped as in Zethus; pygidium triangular, lateral lobes with about eight segments, very much 
deflected, sometimes ending in short points; axis narrow, convex, with very numerous, fine segmental lines, 
often only indicated at the sides, leaving a smooth space down the middle. 
This genus has been confounded with Cybele of Lovén (Zethus Pand.), from which it differs in the 
course of the eye-line. 
Encrinurus punctatus (Briinn. Sp.) 
Ref. and Syn.—Entomostracites punctatus Wahlenberg, Nov. Acta Upsal. 2. Stokesii M*Coy, Syn. 
Sil. Fos. Ivel. t. 4. f.15 (not Cybele punctata Fletcher, Geol. Jour. Vol. VI. t. 32. fig. 1 to 5). 
Sp. Ch—Entire animal elongate, ovate, more than twice as long as wide; cephalic shield semielliptical, 
length more than half the width, coarsely tuberculated, except the posterior margin, which is broad and 
smooth; body-rings broad, smooth, lateral lobes scarcely wider than the axis; pygidiwm triangular, pointed, 
a little longer than wide, having about eight narrow, nearly smooth ribs on each side, bent backwards 
and much downwards at their ends, the intervening spaces nearly as wide as the ribs, concave, smooth, 
coming off from the axis at an angle of about 45° (the upper ones rather more, those towards the apex 
less), the last few embracing the end of the tail; axis with a narrow smooth space down the middle, on which 
are six or seven small tubercles, each side marked with about twenty-eight segmental furrows, one pair 
corresponding to each tubercle, and usually three or four pair between one tubercle and the next. Length 
of entire animal two inches two lines, of pygidium, seven and half lines. 
I have figured the perfect animal for the first time in my “ Synopsis of the Silurian Fossils of Ireland,” 
under the name F. Stokesii, a name which I gave from the difficulty of fixing what was the true species of 
Briinnich and Wahlenberg, as I was acquainted with many unpublished forms, all sufficiently like to 
have been confounded with that species. I have since, however, examined so many specimens identical 
with this, from his original locality, Gothland, that I believe I may safely recur to the old specific name, 
though the accordance is not at all perfect between the species and the account or figure either of Wah- 
lenberg, in the “ Nova Acta Reg. Soc.” &c., Upsaliensis, or of Dalmann; the latter, however, agrees with 
the former, and shews the smooth body-rings, which separate the species so widely from that figured in 
