SUMMAUY. 
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Family IX.— ECHINOLAMPIDiE, Wright (Vol. I, p. 389). 
Test thin, oval or subpentagonal ; upper surface depressed, convex, or conoidal ; 
vertex usually excentric surface bearing small, often perforated, tubercles. Ambulacral 
areas petaloid on upper surface, straight or slightly petaloid on lower. Oral opening 
small and lobed. Jaws absent. Anal opening marginal, supra-marginal, or infra- 
marginal, not in a sulcus. The Echinolampidse range from the Oolitic to the existing 
period. One British Oolitic genus (Pygurus) and six species. 
Genus 21. — Pygurus, d' OrUgny (Vol. I, p. 391). 
Test thin, large, discoidal, subpentagonal ; upper surface slightly conical, under 
surface concave and undulating, rostrated behind, sulcated in front. Tubercles small, 
perforated, larger on under than upper surface. Ambulacral areas distinctly petaloid on 
upper, subpetaloid on lower surface. Pores in a single series, until near the oral opening, 
there becoming closely crowded in triple oblique ranks. Oral opening pentagonal and 
excentric, strongly lobed. Jaws absent. Anal opening oval, infra-marginal, sometimes cor- 
responding to, sometimes transverse to, the direction of the longest axis of the base of the 
test. Apical disc small. Genus found in the Oolitic and Cretaceous strata. Six British 
Oolitic species (Vol. I, pp. 392—405, 467). 
Order II.—ASTEROIDEA, Wrigld (Vol. I, p. 4, Vol. II, pp. 1—22). 
Body stellate, depressed, provided with five or more hollow arms {rays) containing 
(in the living state) prolongations of the viscera. Mouth {oral opening') always central on 
the under side, and sometimes serving as an anal opening as well. Anal opening, when 
present, subcentral on the upper side. Skeleton consisting of many sohd calcareous 
pieces, variable as to number, size, and position. Integument {perisome) coriaceous (in 
the living state), and studded with calcareous spines of various forms, and also with 
tubercles carrying a crown of short bristly spines {paxilla). Rays grooved and pierced 
at the centre of the under surface with two or four sets of pores for the admission (in 
the living state) of retractile tubular suckers, which pass between the edges of internal 
ossicles and not through them. Upper surface of body marked by one or more madre- 
poriform tubercles near the angle between two rays. Eyes (in the living state) generally 
present at the extremity of the rays. No dental apparatus. Small, pincers-like bodies 
supported on slender flexible stems {pedicellarim), on the integument surrounding the 
mouth and bases of spines. Movement of the body performed by the suckers and spines. 
