REPORT ON THE ASTEROIDEA. 245 
ance to the plate in question if my observations had been limited to a single species, but 
I have detected the presence of the intermediate plate in every species I have examined 
critically (small and more or less aborted in some cases it is true, but present in all); and 
I can assert its existence in all the forms included in the following synoptic table :— 
Synopsis of the Species included in the Genus Luidia herein described. 
A. Certain paxille bearing a large central spine on the tabulum. 
a. Rays eight to ten. Spine-bearing paxille separated from the marginal plates by 
three longitudinal series of plain paxille. Plain paxille on the median 
area of the ray with several papilliform granules on the tabulum, scarcely 
larger than the encircling series. Infero-marginal plates with five spines 
gradually increasing in size as they approach the margin of the ray. 
Often two pedicellarie behind, and forming a serial line with, the spines 
composing the adambulacral armature. : aspera. 
b. Rays five. Spine-bearing paxille separated from ce fare sal pintes ie = 
longitudinal series of plain paxille. Plain paxille on the median area 
of the ray with one large tubercle-like central granule. Infero-marginal 
plates with the lateral (and sometimes a second spine) much longer than 
the others. One pedicellaria behind the adambulacral armature, and often 
absent . 5 : : ; : : 5 : 5 : alternata. 
B. Paxille without a large central epinelée 
a. Paxille with a quadrate tabulum. 
a, Lateral spine very short, compressed and robust. Forficiform pedicellaria 
on the infero-marginal plates. Valvate pedicellariz above the infero- 
marginal plates. : 0 » 6 j : ; : limbata. 
b. Lateral spine long, delicate, Gao No forficiform pedicellarie on the 
infero-marginal plates, No valvate pedicellaria present . ; F clathrata. 
b. Paxille with a stellate crown. 
a. Adambulacral armature forming a single transverse series continuous with 
the spines on the infero-marginal plates. 
@, Seven rays. Pedicellarie three-jawed. 
i. One spine on the actinal area of the adambulacral plates, 
long, robust, cylindrical, sometimes with a small unequal 
companion. Pedicellariw very large, three-jawed, nut- 
shaped, very broad at the base, nearly as broad as long. 
Infero-marginal plates with three or four spines, the 
outer two or three subequal, the lateral or median one 
the longest . 5 : : , . : 5 ciliaris, 
8. Five rays. Pedicellari two- nee 
i. One spine on the actinal area of the adambulacral plates. 
Pedicellarie long and spine-like. 
1. The actinal spine of the adambulacral armature short, 
robust, conical. The pedicellarie with delicate 
spine-like jaws. Infero-marginal plates with three 
spines, the lateral one long, the other two much 
smaller, less than the actinal spine of the adambu- 
lacral armature . : : ; longispina. 
. Two spines on the actinal area of the raseeeclacral plates. 
Pedicellarie short and papilliform. 
