40 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 
Station 5607; Gulf of Tomini, Celebes; Binang Unang Island (E.) 
bearing S. 36° E., 5 miles distant (lat. 0°04’00’’ S., long. 121°36’00’” 
E.) ; 1,891 meters; fine sand; November 18, 1909. Two adult speci- 
mens, one of them abnormal. 
Station 5619; Molucca passage; Mareh Island (S.) bearing 8. 78° 
E., 7 miles distant (lat. 0°35’00’ N., long. 127°14’40’" E.); 795 
meters; fine gray sand and mud; November 27, 1909. One fine adult 
and one young specimen. 
Station 5664; Macassar Strait; Kapoposang Light bearing N. 66° 
E., 3.8 miles distant (lat. 4°43’22”” §., long. 118°53’18’" E.); 731 
meters; bottom temperature 6.28° C.; hard bottom; December 28, 
1909. Twelve young specimens. 
Remarks—One of the specimens from station 5607 was remark- 
able in having the genital pores, situated in the middle of the genital 
plates, very small. On opening it, I found no traces of the genital 
organs, which ordinarily are quite easy to find, even in much smaller 
specimens. There can be no doubt that this specimen is abnormal— 
castrated for some reason. No parasites were found on or within it. 
There is a pronounced sexual difference, the genital pores of the 
female being situated in the middle, or nearer the inner edge, the 
very small pores of the male at the very tip of the genital plates. 
Such sexual difference is found also in the other species of Prionechi- 
nus and must be regarded as an important character of the genus 
Prionechinus. 
PRIONECHINUS SAGITTIGER A. Agassiz 
Prionechinus sagittiger A. AGAsstz, Challenger Reports, Zoology, vol. 3, pt. 9, 
p. 109, pl. 6a, figs. 11-14, 1881.—MortEensen, Ingolf Echinoidea, pt. 1, p. 82, 
pl. 7, figs. 21, 25, 29, 1908.—pr Mriserr, Siboga Echinoidea, p. 70, pl. 16, 
figs. 245-249, 1904.—D6perLEIN, Wiss. Ergebn. Tiefsee-Exped., vol. 5, Lief. 2, 
p. 196, pl. 25, fig. 1; pl. 35, fig. 6; pl. 46, fig. 5, 1906—H. L. CuapxK, 
Hawaiian and other Pacific Echini, Pedinidae, etc., p. 504, 1912; Catalogue 
of the recent sea-urchins in the British Museum, 1925, p. 79. 
Locality.—Station 5661; Flores Sea; Cape Lassa bearing N. 21° 
K., 12.5 miles distant (lat. 5°49’40’’ S., long. 120°24’30” EH.) ; 329 
meters; hard bottom; December 20, 1909. One young specimen. 
Genus ORECHINUS Daderlein 
ORECHINUS MONOLINI (A. Agassiz) 
Trigonocidaris monolini A. AGASSIz, Challenger Reports, Zoology, vol. 3, pt. 9, 
Echinoidea, p. 111, pl. 6a, figs. 8-10, 1881. 
Genocidaris monolini DE MEIJERE, Siboga HEchinoidea, p. 74, pl. 4, figs. 35-37; 
pl. 16, figs. 856-268, 1904. 
Orechinus monolinit DODERLEIN, Wiss. Ergebn. Tiefsee-Exped., vol. 5, Lief. 2, 
Dp. 196) ple 25, fies Dy “pli 35,7 fie 6; YphraGe fieton 1906: —-E Eh. (CraRK, 
Hawaiian and other Pacific Echini, Pedinidae, ete., p. 300, pl. 98, figs. 27-81, 
1912. 
