272 DEEP-SEA P-ISHES OF THE ATLANTIC BASIN. 



and mandible; vomer and palate toothless. Preoperculnm armed with short, stout, simple 

 spines. Bones of the sknll thin. Gills 3i; no slit behind the last. Gill openings wide; 

 the membranes broadly attached to the isthmus. Gill-rakers tubercular, in moderate 

 number. Spinous dorsal low, sejjarated by a deep notch from the soft dorsal. Pectorals 

 procurreut in front. Ventrals small; caudal rounded. Vent distant from the anal origin. 

 Head and body naked. Lateral line consisting of a series of large pores. 



This genus is represented by seven examples of the type species, M. zoniirns. Beau, 

 taken by the Albatro.ss on August 1>, 1S8S, from station 2853, oft' Trinity Islands, in 50° 

 N. lat., 154° w. Ion., at a depth of 159 fathoms. 



Family CYCLOPTERID^E. 



Cycloplerida, Bonaparte, Cat. Metodico, 1846. 64. — Gill, Ait. Faniilie.s of Fishes, 1872, x.\.\; Century Dic- 

 tionary, 1424. — JoKDA.v anil Gilbert, Bull, xvi, U. S. Nat. Mus., 744.— Gill, Proc. r. S. Nat. Mus., xiii, 

 366, 1891. 



Cyclopterina, Gunther, Cat. Fish. Brit. Mus., iii, 154. 



Cycloptcroidi-a, with a feebly ossified skeleton and ventricose body, covered with thick 

 skin, which may be either smooth, tubercular, or spinous. Head short, tliick; suborbital 

 stay present, thin and flatfish. Mouth small, terminal; jaws lateral, with slender teeth in 

 bands; vomer and palatines toothless. Gill openings narrow, nn'mbranes broadly joined 

 to isthmus and shoulder girdle. Branchiostegals (i. Dorsal tin long, its anterior portion 

 of flexible spines, sometimes hidden in adult by a fleshy hump, sometimes wanting. Soft 

 dorsal small, opposite and similar to anal. Caudal rounded. Ventral rudimentary, form- 

 ing the bony center of a thoracic sucking disk. Pectorals short, low, with bases broad and 

 procurrent. Pyloric caeca numerous. Vertebrje 12-)-16. 



KEY TO THE GENERA OF CYCLOPTERID^. 

 (From Jordan and Gilbert, rearranged.) 



I. Spinous dorsal present, sometimes di.sappearing with age; skin tubi-rcuhite. 



A. Dorsal spines in adult hidden ill a lieshy hump. Ventral disk small C'yci.optercs 



B. Dorsal spines not hidden in adult; gill opening a small slit; ventral disk large ErMU uoTRKMts 



II. Spinous dorsal wanting; skin smooth or nearly 30 [CYCLOPTERicnTiiYS] 



Genus EUMICROTREMUS, Gill. 



Eumicroiremus, Gill, Proc. Acad. Nat. Sci., Phila., 1864, 190. — ^Collett, Norsk. Nordh. Exp., 67.— Goode 

 and Bean, Bull. Esses Inst, xi, 12. — Jordan and Gilbert, Bull, xvi, U. S. Nat. Mus.. 9.57. 



Cyclopterids with a spinous dorsal, which is sometimes in adults hidden in the skin, 

 though never disappearing with age. Skin thick, armed with series of bony tubercles. 

 Gill opening a small slit on level of eye. Ventral disk large. 



EUMICROTREMUS SPINOSUS, (MOller), Gill. (Figure 250.) 



Cydopterus spinosm, MiJLLER, Prodromus Zoologiae Danicie, 1777, ix.— Gaimard, Voy. Skand., PoisB., 

 pi. IV, fig. 2— GttNTHER, Cat. Fish. Brit. Mus.. iii, 1861, 157; Proc. ZoiJl. Soe., London, 1877, 293, 

 fig. (young); ibid., 475; Challenger Report, xxii, 1887, 66.— Malmgren, Ofvers. K. Vet. Ak. Forh., 

 1864,489, .sp. n.— Frisch, Peterm. Geogr. Mitth. 1865, Erg. Heft. Nr. 16, 35.— Heuglin, Fauna and Flora 

 in Geologic Spitzbergen in Novaja Semlja, 1874, 211.— Jordan and Gilbert, Bull, xvi, U. S. N. M., 746. 

 Lumpus spinosux, Storer, Syn. Fish. N. A., 1846, 230. 



Eumicrolremus npinosm, Gill, Proc. Acad. Nat. Sci., Phila., 1864, 190.— Collett, Norske Noidh. Exped., 

 Fisk., 67, pi. II, fig. 13.— Goode and Bean, Bull. Essex Inst., xi, 12.— Jordan aud Gilbert, Bull, xvi, 

 U. S. N. M., 957.— Jordan, Cat. Fish. N. A., 116. 



Body orbicular, cuboid anteriorly, its heiglit nearly one-half of its length, which is .3 

 times the length of the head; base of spinous dorsal and body behind vent abruptly com- 

 pressed; teeth in narrow bands; gill openings on a level with eye, slightly narrower than 

 orbit. Spinous dorsal not hidden, covered with rough tubercles, simihir to those on body, 

 but smaller; width of ventral disk slightly less than its length, and somewhat less than 



