LOPHIOMUS SPILURUS. 77 



The vertical range of the Halieutoids had been carried down to 902 

 fathoms ; by the " Albatross " it is extended to 1360 fathoms, the greatest 

 depth yet attained for the subdivision. The species from the upper levels 

 exliibit the colors and ornamentation characteristic of those affected by 

 the light of the sun. Most often the spots are absent from' forms below 

 250 fiithoms but in case of Malthopsis sjnnidosa, Plate XXI., spots are 

 present at 511. At great depths dull brown to black, probably phosphor- 

 escent in life, appears most common, but in case of Halieutopsis there was 

 a brilliant rose color, as on Chaunax coloratus of the Lophioids. Larger eyes 

 most often appear among the species from greater depths, but the species 

 taken at the greatest depth is the one with the smallest eye in tlie division. 

 The esca (bait) of the illicium appears to be highly colored in some forms, 

 and probably in all is more or less luminous. 



So far as affinities are concerned, those of Lophiomus and Malthopsis 

 reach toward species of the western Pacific, while those of Dolopichthys 

 Dibranchus and Oncocephalus are closer to species across the isthmus in 

 the Atlantic. The nearest relationship occurs between Oncocephalus vesper- 

 iilio and 0. porrectiis. 



LOPHIID.E. 

 Lophiomus spilurus sp. w. 



Br. r. 6 ; D. 3 + 3 + 8 ; A. 6 ; V. 6 ; P. 17; C. 8 ; Vert. 18. 



The shape of this species does not differ greatly from that of L. cauli- 

 naris. Evidently the two species are closely allied, but the present par- 

 takes more of the characteristics of forms belonging to great depths. L. 

 spilurus is distinguished by a long slender simple first dorsal spine ending in 

 a filament without a fleshy bait, by much larger teeth in specimens of equal 

 size, by a simple humeral spine with a single backward directed point, and 

 by the coloration. Disk about three eighths of the total length, longer than 

 broad, much depressed, depth hardly one third of the width. Forehead 

 troughlike, concave ; face concave in front of the orbit. Snout broad, lower 

 jaws much the longer, lower teeth exposed in front of the upper jaws, entire 

 length in front of the orbits less than twice the length of the eye, width 

 between the prenarial spines equal to that between the large spines above 

 the hind edge of the orbit, symphyseal angle prominent. Mouth very wide, 

 articular angle opposite the hinder part of the eye. Teeth imequal, acicular, 



