318 U.S. NATIONAL MUSEUM BULLETIN 236 



Maldive Archipelago (Sewell, 1940); Spencer Gulf and Sellick Beach in 

 South Australia (NichoUs, 1941); Port Denison in Western Australia 

 (NichoUs, 1945); and Puget Sound in the United States (Wieser, 1959). 

 The occurrence of this species at Ifaluk fits admirably in the general 

 pattern of its distribution over the tropical and temperate regions of 

 the Pacific, Indian, and Atlantic Oceans. In the Ifaluk collections it 

 predominates in sand samples taken at various intervals from the reef 

 margin, but it also occurs in a washing of caulerpas and in crevices 

 near the reef margin. The specimens, generally, are slightly smaller 

 than those recorded by Sewell (9 0.80 mm.) and NichoUs (9 0.90-1.02 

 mm., cf 0.90 mm.). 



Laophonte dinocerata Monard, 1926 



Figures 125, 126 

 Laophonte dinocerata Monard, 1926a, p. 619, figs. 1-10. — Monard, 1928, p. 420, 



fig. 41 (no. 2).— van Douwe, 1929, p. 285.— Monard, 1935, p. 60; 1935a, p. 69; 



1937, p. 70. 

 Laophonte inornata Lang, 1948, p. 1355, fig. 546 (in part). 



Material. — Loc. 709, 1 ad. 9, 0.47 mm. 



Description. — The following is based on the above-mentioned 

 specimen, which has been dissected and mounted. 



Adult female, total length 0.47 mm.; greatest diameter 0.14 mm.; 

 length of longest furcal seta 0.30 mm. 



General shape of body elongate, slightly compressed dorso-ventrally, 

 with greatest diameter at end of cephalothorax and very gradually 

 narrowing posteriorly, at genital somite distinctly widened (fig. 125a). 

 Head and 1st thoracic somite fused to form cephalic somite, which 

 is as long as combined lengths of thoracic somites 2 and 4. Frontal 

 part of cephalic somite narrowing, rostrum broad, triangular structure 

 with very broad base and rounded apex, incised on both sides and 

 provided there with small hair. Back in lateral aspect almost straight, 

 rostrum pointing forward and very slightly downward (fig. 1256). 

 2nd to 5th thoracic somites of nearly same length, at distal end of 

 dorsal wall set with fine spinules. Epimeral plates of these somites 

 scarcely produced, insertion of legs distinctly visible laterally. 3rd to 

 5th thoracic somites dorsolaterally produced into backwardly 

 directed, chitinized spiniform processes, distinctly visible in lateral 

 and dorsal view. The exact size of these processes can best be judged 

 from figures 125a, 6; they give the cephalothorax a very characteristic 

 appearance. Total length of cephalothorax IK times length of 

 abdomen. 



Genital somite composed of fused abdominal somites 1 and 2 ; line of 

 fusion distinctly visible dorsally and bordered with fine spinules. 1st 

 abdominal somite slightly and 2nd abdominal somite distinctly 

 laterally produced; wing-shaped part of 2nd abdominal somite set 



