100 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 
Family ARACHNOIDIDAE 
Genus ARACHNOIDES Leske 
ARACHNOIDES PLACENTA (Linnacus) 
Arachnoides placenta A. AGAssiz, Revision of the Echini, p. 580, 1873 (pro parte; 
non pl. 13b, figs. 14=A. zelandiae Gray).—H. L. Ciark, Hawaiian and other 
Pacific Echini, Clypeastridae . . . Scutellidae, p. 43, 1914 (pro parte; non pl. 
125, figs. 1-3=A. zelandiae) ; Catalogue of the Recent sea-urchins in the Brit- 
ish Museum, p. 154, 1925. 
Only a single broken test of this species was collected by the Alba- 
tross, at Verde del Sur Island, Palawan, probably on the beach. 
Family LAGANIDAE 
Genus PERONELLA Gray 
PERONELLA LESUEURI (Valenciennes) 
Laganum lesueuri L. AGAssiz, Monographie des scutelles, p. 116, pl. 24, figs. 3-6, 
1841.—pE Mertsrerr, Siboga Echinoidea, p. 122, pl. 6, figs. 63, 67, 70; pl. 18, 
figs. 829-333, 1904. 
Laganum rostratum lL. AGAss1z, Monographie des scutelles, p. 118, pl. 25, 1841. 
Peronella decagonalis A. AGASSIz, Revision of the Echini, pp. 148, 520, pl. 13e, 
figs. 8-11, 1873. 
Peronella rostrata A. AGASSIZ, Revision of the Echini, pp. 149, 523, 1873. 
Peronella lesueurt H. L. CLARK, Hawaiian and other Pacific Hchini, Clypeastridae 
... scutellidae, p. 58, pl. 124, figs. 28, 24, 1914; Catalogue of the Recent sea- 
urchins in the British Museum, p. 159, 1925; Mem. Mus. Comp. Zool., vol. 
55, p. 417, pl. 15, fig. 3, 1938. 
Localities —Station 5161, Tinakta Island (lat. 5°10’ N., long. 119°53’ 
EK.) ; 29 meters; February 22, 1908. Six dead tests. 
Station 5181, off eastern Panay (lat. 11°37’ N., long. 123°27’ E.) ; 48 
meters; March 27, 1908. Ten specimens, seven of which are dead 
tests. 
Station 5276, China Sea, off Luzén (lat. 13°49’ N., long 120°15’ E.) ; 
33 meters; July 17, 1908. Four specimens. 
Remarks.—The specimens from stations 5161 and 5181 are of the 
variety rostrata (A. Agassiz). 
I agree with de Meijere and Clark that the Zaganwm rostratum of 
L. Agassiz cannot be maintained as distinct from his Z. Zesueur; still, 
the slightly prominent posterior end of the test gives so characteristic 
a general appearance that there is good reason for recognizing this 
form as a separate variety. 
The largest of the specimens of the variety, a dead test, is 45 mm. 
long, much smaller than the type, which is 85 mm. long. 
