50 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 
Locality—Station 5109; China Sea, off southern Luzon; Cor- 
regidor Light bearing N. 42° E., 25.8 miles distant (lat. 14°03’45’’ 
N., long 120°16’30’’ E.); 18 meters; coral; January 15, 1908. One 
young specimen. 
Genus SELENECHINUS de Meijere 
SELENECHINUS ARMATUS de Meijere 
Selenechinus armatus DE MEIJERE, Siboga Echinoidea, p. 99, pl. 5, figs. 38, 39; 
pl. 17, figs. 291-299, 1904. 
No locality Two specimens. 
Remarks.—The collection contains two specimens, the larger of 
them 100 mm. in diameter, agreeing completely with the description 
and figures given by de Meijere. Unfortunately they are without 
any label, which is the more regrettable since the type and only speci- 
men hitherto recorded likewise had no label, so that de Meijere could 
state only that most probably it came from the Jolo Sea. This may 
very probably be the case also with the Albatross specimens, but 
there is no certainty, and likewise the depth at which it was taken 
remains unknown. 
Genus ECHINOSTREPHUS A. Agassiz 
ECHINOSTREPHUS FORMOSUS, new species 
Characters——The test is very low, only 5 mm. in height, with a 
horizontal diameter of 13 mm. The sides are regularly rounded, 
not subvertical as is usual in Echinostrephus, and the greatest 
diameter is at the ambitus, not on the aboral side. The shape of 
the test is thus very different from the usual in Lchinostrephus. 
There are four pore pairs on the ambulacral plates of the aboral 
side. Miliary tubercles are few, none separating the primary inter- 
ambulacral tubercles as is the case in E'chinostrephus molaris. The 
genital plates carry each two tubercles at their inner edge. Peri- 
proctal plates are few, rather large. There is no anal proboscis. The 
pedicellariae are not peculiar. The spines are as usual, the aboral 
ones the longest. They are purple with the tip white. The color 
of the test is a light bluish purplish, the apical system reddish 
purplish. 
Locality.—Station 5558; in the vicinity of Jolo; Cabalian Point 
bearing S. 1.1 miles distant (lat. 5°51’83’’ N., long. 121°00’58’’ E.) ; 
27 meters; coral; September 17, 1909. One specimen, the type. 
Remarks.—This very handsome species differs particularly by the 
unusual shape of the test very conspicuously from the other species 
of the genus E'chinostrephus. Probably it is only a young specimen, 
but the genital pores have been formed, though still quite small. 
