548 Bulletin 42, United States National Museum. 



255. RONDELETIA, Goode & Bean. 



Rondeletio, Goode & Bean, Proc. U. S. Nat. Miis., 1S94 (1895\ 454, {bicolor); and in Oceanic 

 Ichthyology, G8, 1895. 



Body oblong, compressed, scaleless. Mouth large, lower jaw slightly 

 projecting. Teeth in bands, coarsely granular in the jaws ; vomer and 

 jialatines toothless; a row of large mucous pores on the lower surface of 

 the mandible, and extending upward on the preoperculum. Posterior 

 nostril with a slender filament anteriorly. Eyes moderate, near the 

 dorsal profile. Snout rather long, obtuse. Supraoccipital bones with a 

 pair of strong spines projecting horizontally forward over the orbit. Gill 

 membranes entirely separate; gill rakers numerous, rather long and 

 slender ; gills 4, a narrow slit behind the fourth. Brauchiostegals 7. 

 Opercular bones thin, membranous. Dorsal short, rather low, opposite 

 and similar to the anal ; pectorals and ventrals small ; caudal small, 

 probably forked. No vestiges of a lateral line. (Dedicated to Guillaume 

 Rondelet, " the great French ichthyologist of the seventeenth century," 

 one of the ablest of the "Fathers of Ichthyology.") 



825. RONDELETIA BICOLOR, Gundo .t Bean. 



Head about 2 in total length; depth 3; eye 6; snout 3. B. 7; D. 14; 

 A. 14 ; P. 9 ; V. 5. Maxillary reaching to below the hind margin of eye. 

 Origin of dorsal fin nearly opposite vent; origin of anal immediately 

 behind vent, the terminations of the two opi^osite. Fins low, the rays 

 pointing horizontally backward ; longest dorsal ray 5 in head, longest 

 anal ray 4 ; pectoral fin inserted below middle of body and under end of 

 opercular flap, its length nearly i that of head ; ventrals inserted 

 behind middle of total length, and still farther behind tips of the 

 extended pectorals, their length about f that of head, and when extended, 

 reaching beyond vent. Color purplish black, with cherry-colored mar- 

 gins to the fins ; whitish in spirits. 



A single specimen 4^ inches in length, Avas taken by the Fish Com- 

 mission steamer Albatross at station 2724, at a depth of 1,641. fathoms. 

 (Goode & Bean.) {bicolor, two-colored.) 



Rondelelia bicolor, GoODK & Bean, Proc. U. S. Nat. Mus., 1894 (1895), 454, jil. 17, fig. 1; and in 

 Oceanic Ichthyology, 68, fig. 77, 1895. (Type, No. 38202. Coll. Albatross). 



Family LXXIV. CETOMIMID^. 



Body somewhat compressed, scaleless ; head naked ; lateral line con- 

 spicuous. No barbels. Mouth exceedingly large; the margin of the 

 upper jaw formed by the iiremaxillaries only ; the lower jaw strongly 

 curved, and slightly projecting beyond the upper. Teeth in jaws in 

 bands, granular; vomer, palatines, pterygoids, and also the first gill arch 

 and the lingual bones (which are greatly enlarged), as well as the upper 

 pharyngeals, covered with teeth of a similar character. Opercular appa- 

 ratus incomplete, its bones very thin, membrane-like. No adipose fin ; 

 dorsal fin far back, short, high, inserted opposite the anal, which it 

 resembles ; pectorals short, placed rather low ; ventrals absent. Gill 

 opening inmiense, the membranes deeply cleft, free from the isthmus. 



