REPORT ON THE ASTEROIDEA. 
with adambulacral plates a a Pedicellariz valvate, foraminate 
or excavate : . 5 : : : . 
_ A. Marginal plates large Aeal conan ronal with the axes of the plates of 
the two series usually in parallel planes. 
a. Apical plates decrescent. Abactinal skeleton with simple spini- 
ferous spicules, with pseudo-paxille, or true columnar 
paxille. Tegumentary developments usually spiniform. 
a. Marginal plates thin and lamelliform, naked, or covered only 
with membrane. Actinal areas paved with thin squami- 
form plates covered with delicate membrane. Cribri- 
form organs present. Adambulacral plates with a 
simple marginal armature, uniserial ‘ : 
b. Marginal plates thick and massive, covered with spines or 
papilla. Actinal areas small, plates when present 
covered with spines. No cribriform organs. Adam- 
bulacral plates with a complex armature, grouped or 
in several series, 
a Proctuchous. Devoid of superambulacral plates. Adam- 
bulacral plates large and not compressed. Pedi- 
cellariz usually present : : : 
B. Aproctuchous. With superambulacral lstees Adam- 
bulacral plates short, and more or less compressed. 
Pedicellariz rarely present . ; 
b. Apical plates often increscent. Abactinal skeleton dossellate. coe 
mentary developments usually graniform. Actinal inter- 
radial areas well developed. 
a. Abactinal skeleton tessellate, the plates often more or less 
tabulate, with co-ordinated granules simulating paxille 
b, Abactinal skeleton stellato-reticulate. 
a, Abactinal plates with granules and tubercles. Actinal 
intermediate plates with large valvate pedicellarie 
8. Abactinal plates with large conical spiniform tubercles. 
Actinal intermediate plates devoid of large valvate 
pedicellariz : 
c. Abactinal skeleton tessellate, the plates Steen regular mad 
only partially contingent, covered with skin : 
B. Marginal plates comparatively small and inconspicuous ; with the axes 
of the plates of the two series convergent and not in parallel 
planes. Abactinal skeleton with lamelliform plates, imbricating, 
notched on one side, with spines on the free margins. Spines on 
the actinal intermediate plates. No pedicellaria 
II. Marginal plates small and inconspicuous. Papule not confined to the area 
circumscribed by the supero-marginal plates, but often present between the 
marginal plates and on the actinal surface. Ambulacral plates more or less 
crowded and narrow. Actinostomial ring with ambulacral or adambula- 
cral plates prominent. Pedicellariz pedunculate or sessile, not foraminate 
A. Marginal plates small but persistent. Abactinal skeleton more or less 
fully developed. Parambulacral and actinal intermediate plates 
present; one or both more or less fully represented. Interbra- 
chial septa usually present. 
(ZOOL. CHALL. EXP.—PART LI.—1888,) 
xli 
Order PHANEROZONIA. 
PORCELLANASTERID2. 
ARCHASTERID &. 
ASTROPECTINIDA, 
PENTAGONASTERIDE. 
ANTHENEIDA, 
PENTACEROTIDA. 
GYMNASTERIID®. 
ASTERINID®. 
Order CRYPTOZONTA. 
