60 U.S. NATIONAL MUSEUM BULLETIN 2 02 Vol. 3 



surface at base, near middle, and near tips of rays; first dorsal spine 

 slightly blackish or brownish; lips barred. 



Color when alive. — The darker markings are light yellowish brown; 

 pale areas and blotches white. 



Ecology. — This species occurs in loose sandy areas between coral 

 heads. 



Remarks. — It is with regret that we add a new name to the ah'eady 

 confused literature for this family. After studying what we think are 

 all of the descriptions for known species referrable to the genus 

 Thysanophrys, as recognized and defined in the key to genera, we 

 find no species already described that is close to this one from the 

 northern Marshall Islands. T. chiltonae is characterized by its long 

 snout, large orbits, and very narrow interorbital space in conjunction 

 with a spine on the preorbital in front of eye in line with another on 

 ridge of first suborbital below front of eye, then 4 or 5 more spines on 

 suborbital ridge mostly behind eye, and a broad opercular membrane 

 with a deep notch. We can find no other species in the genus 

 Thysanophrys that has such characters in combinations with 53 or 54 

 pores in the lateral line. Platycephalus cooperi Regan is closely 

 related but has 58 to 65 pores in lateral line; the minor ridges of the 

 head are granulated, and the eye is about 1.1 in snout. Although 

 Insidiator diversidens has 52 or 53 pores in the lateral line, the sub- 

 orbital ridges are serrated throughout their length, with only about 2 

 or 3 stronger spines, and the first 10 to 15 scales of lateral line bear 

 small spines, unlike T. chiltonae. 



THYSANOPHRYS ARENICOLA, new species 



Plate 130,B,C; Figure 148 



Holotype. — USNM 141007, Rongelap Atoll, Naen Island, lagoon 

 reef, July 30, S-46-302, Herald, standard length 128 mm. 



Paratypes. — USNM 112391 taken with holotype and bearing same 

 data; standard length 105 mm.; USNM 112392, Rongelap Atoll, 

 Arbor Island, ocean reef, June 16, S-46-213, Schultz, 1 specimen, 56 

 mm.; USNM 141733, Rongelap Atoll, Mellu Island, lagoon reef, 

 June 19, S-46-220, Schultz and Herald, 1 specimen, 25 mm.; USNM 

 112393 Rongerik Atoll, Bock Island, June 27, S-46-237, Schultz and 

 Herald, 1 specimen, 72 mm.; Rongerik Atoll, Latoback Island, 

 Aug. 16, 1947, Univ. Washington, standard length 173 mm.; Bikini 

 Atoll, Bikini Island, June 28, 1946, Univ. Washington, 4 specimens, 

 121 to 176 mm.; USNM 152919, Bikini Atoll, Bikini-Amen reef, Aug. 

 2, 1946, Univ. Washington, 1 specimen, 75 mm.; USNM 152918, 

 Eniwetok Atoll, Biijiri Island, July 26, 1948, Univ. Washington, 1 

 specimen, 75 mm. 



Description. — The following counts are recorded first for the holo- 



