204 
POPULAR SCIENCE REVIEW. 
DESCRIPTION OF THE PLATES. 
The following letters denote the same parts throughout all the plates, 
a. b. Axial body cavity, a. c. Axial cords of the skeleton, a. t. Anal 
tube. b. Basals. bt\, br 2 , br 3 , &c. First, second, and third brachials, &c. 
bv. Radial blood-vessel. c. c. Cceliac canal, cd. Centrodorsal piece. 
ch. Chambered organ. ci. Cirrus, ci. c. Ciliated cups. c. p. Central 
plexus. c. pi. Covering-plates of food-groove. c. v. Cirrus-vessel. 
d. Digestive tube. e. Epithelial lining of food-groove, f. g. Food-groove. 
g.c. Genital canal, m. Mouth, n.v. Ventral nerve, ov. Ovary, pi. Pin- 
nule. p. j. Pinnule-joint. r lf r 2 , r 3 . First, second, and third radials. 
ro. Rosette, s. Sacculi. sh. Fibrillar sheath of chambered organ, s. pi. 
Side-Mates of food-groove, st. c. Sub-tentacular canal, t. Tentacle. 
w. p. Water-pores. w.t. Water-tubes, w. v. Water-vessel. 
PLATE V. 
The three figures on this plate are copied , with slight variations, from Dr. H. 
Ludwig's 1 Beitrdge zur Anatomie der Crinoideen,' Morphologische 
Studien an Echinodermen, Vol. I. Leipzig, 1877-1879. 
Fig. 1. Diagrammatic vertical section through the body of Ant. rosacea. 
On the right side the section passes along a ray, and on the left 
side it is interradial. 
Explanation of the shading : black, nervous system ; red, blood- 
vascular system ; oblique shading, water-vascular system. 
Fig. 2. Cross section of a pinnule of a sexually mature female Ant. 
Eschrichtii. x 50. 
The exigencies of space have necessitated the reversal of this 
figure. The skeleton should be downwards, and the food-grove 
upwards, as in fig. 1. 
Fig. 3. Diagram of the distribution of the axial cords within the calyx of 
Comatula, showing their origin in the fibrillar envelope of the 
chambered organ. 
PLATE VI. 
Figures 1, 2, 10 and 12, by permission of the Lords Commissioners of the 
Treasury. 
Fig. 1. Piece of a grooved arm of a new Actinometra from the Philippines, 
seen from above, x 4. 
Fig. 2. Piece of an ungrooved arm of the same specimen, x 4. 
Fig. 3. Calyx of a recent Pentacrinus, from the side, x 4. 
Figs. 4 and 5. Side and under views of the calyx of Antedon cheltonensis 
from the Inferior Oolite of Cheltenham, x 4. 
Fig. 0. Under view of the calyx of Ant. celtica, showing the rosette (ro) 
in the centre of the ring of first radials (t\). x 7. 
Fig. 7. Side view of the united calyx and centrodorsal piece of the same 
species, x 7. 
Fig. 8. Rosette of Ant. rosacea, seen from above, x 15. 
Fig. 9. Calyx of Ant. scrobiculata, from the White Jura of Wiirttemberg. 
Copied from Goldfiiss. 
Fig. 10. Side view of three joints of a pinnule of a new Antedon from the 
Pacific, showing the side-plates (s. pi.) bounding the food-groove, 
and the covering-plates (c. pi.) which rest upon them. The dark 
spots between every two side-plates indicate the positions of the 
sacculi. x 20. 
Fig. 11. Disc of Act. Solaris, with open food-grooves. Seen from above, 
x 5. 
Fig. 12. Plated disc of a new Antedon from the Pacific, with the food- 
grooves converted into tunnels by the folding down of the covering- 
plates at their sides, x 5^. 
