118 BRITISH PALALOZOIC FOSSILS. (EcninopERMATA. 
into the visceral cavity; a strong perforated articular ridge runs across the top of the scapule (1st secondary 
radials) ; all the plates slightly convex and smooth. 
Distinguished from the C. calyx by its deeply impressed pelvis and long lanceolate primary radials. 
Position and Locality —Not very uncommon in the carboniferous limestone of Derbyshire. 
Explanation of Figures—Plate 3. D. fig. 2. End view of specimen, natural size—Fig. 2@ profile of Do. 
Genus. SYNBATHOCRINUS (Pihill.) 
Gen. Char.—Cup conical; pelvis pentagonal, of one (?) undivided piece, supporting five very thick penta- 
gonal scapule, (1st primary radials) greatly diminishing the internal cavity; the articulations for the arms or 
sueceeding secondary radials extending across their entire width ; joints of rays (secondary and tertiary radials) 
simple. 
SYNBATHOCRINUS conicus (Phill.) 
Ref.—Phill. Geol. York. Vol. I]. t. 4. f. 12, 13. 
Sp. Ch.—Cup rapidly expanding, conical, depth to upper margin of Ist primary radials (scapule) about 
two-thirds the width ; columnar articulation deep, circular, crenulated at the edge, perforation very minute (I 
think I see three divisional lines in the pelvis); scapule (or Ist primary radials) broad, quadrate, of great 
thickness extending nearly into the middle of the cavity (as in Apiocrinus), and having as in that genus a strong 
transverse perforated articular ridge. Length of cup about five lines; surface smooth, (according to Austin 
there is one thick cuneiform arm-joint (2nd primary radial) having two long fingers of one row of joints 
(secondary radials). 
Position and Locality.—Carboniferous limestone, Derbyshire. 
Genus. PLATYCRINUS. (dMill.) 
= (Centrocrinus + Plewrocrinus) Aust. 
Gen. Char.—Column-joints round and radiatingly striated near the pelvis, elliptical and with a thick trans- 
verse articular ridge lower down; pelvis pentagonal of three pieces, often anchylosed into one, supporting five 
broad, equal, subquadrate 1st primary radials or scapulze, each with an excavation for the much narrower 2nd 
primary radial (arm), which gives off from its upper pointed edge two rows of secondary radials of about two 
joints each (hands) which are tentaculated on their inner face ; fingers of double rows of joints, tentaculated, 
and variable in number. 
There are two subgeneric types named by Mr Austin of this genus, one Centrocrinus (or to which the 
name Platycrinus might be restricted if necessary,) having a long tubular central mouth; the other group Pleu- 
rocrinus, in which the mouth forms a simple lateral opening. 
PLATYCRINUS CORONATUS (Gold.) 
Syn. and Ref—Goldfuss, Nova. Acta. Akad. Czes. Leop. Carol. Nat. Cur. Vol. XIX. Pl. 31. f. 8. 
= Platycrinus mucronatus ( Aust.) 
Sp. Ch.—Body small, short, semicylindrical, little wider above than below, visceral portion equalling the 
cup in depth; pelvis thick, flat as if truncated, the margin forming an obtuse tubercle opposite each line of 
division between the Ist primary radials or scapulee, which are thick, nearly square, length and width equal, 
excavation for 2nd primary radials or arm-plate half the depth of the scapulz ({ mouth between one pair of 
arms) ; capital plates large, few, with an obtuse conical protuberance in the centre of each; surface smooth. 
Position and Locality—Rare in the carboniferous limestone of Bolland. (Bristol is the original locality of 
Goldfuss.) 
PLAtTYcrRINuS ELLIPTICUS (Phill.) 
Ref —Phill. Geol. York. Vol. II. t. 3. f. 19 and 21. 
Sp. Ch.—Cup obtusely oval, subcylindrical in the middle, pelvic and pectoral ends equal; Ist primary 
radials (scapula) nearly square, scapular articulation narrow, about one-third the depth of the plate; capital 
