DISCUSSION OF SrECIES AND THEIR DISTRIBUTION. 51 



PTEROTHRISSUS, Hilgendorf. 



Pterothrimis, HlLGE>fDr)Ri-, Act. Soc. Lftopoldiua Carol., xili, Nos, 15, IG, September 3, 1877, IL'7.— Sitz- 



ungsber. Natiirf. Freuuile, 1878, 15G; 1887, 187. 

 Bathythrissa, Guntueu, Auh. and Mag. Nut. Hist., XX, 1877 (November 1), 433.— Challenger Report, xxii, 220. 



" Body covered with .scales of moderate .size; head narrow, obloiiy, with muciferous chan- 

 nels uiiich developed. E^ye large. Month narrow, coregonoid, with bands of luinnte teeth 

 embedded in the thick lips; maxillary with a marginal row of very small teeth. Candal tin 

 forked, with a den.se Liyer of small .scales. Air bladder with very thick walls, termiuatinn- 

 in two short horns in front, pointed behind.'' {(JUiithcr.) 



Pterothrissm was published September 3, 1877, and Bathythrissa^ November 1 1877. 

 (See Sitzungsherkhtc, Naturforschende Freunde, 1887, No. 9, 187, 188.) 



The genus and family are known only from a. single spec-ies, P. (/issn, Hilgendorf 

 (Figure 52) [^Bathythrissa dorsalis, Giinther, Challenger Keport, xxii, 222, pi. lvi, fig. AJ 

 from Japan taken in 315 (?) fathoms. 



Family ARGENTINID,^. 



Argetttininw, Jordan and Gilbert, Bull, xvi, U. S. Nat. Miis., 1883, 288. 

 Argentinidw, GiLi., Smithsonian Report, 1884, 619. Jordan, Cat. Fi.sh. N. A., 1885,42. 



Body elongate; scales cycloid. Head naked. Mouth terminal, small or moderate; the 

 maxiUary forming the lateral margin of the upper jaw; a supplemental maxillary bone; pre- 

 maxillaries not ])rotractile. Teeth in jaws absent. Four gills, a slit behind the last. Pseu 

 dobrjincliia' present. Gill membranes separate, free from the isthnui.s. Branchiostegals 

 six or more. Dorsal short, nearly median ; adipose fin present. Caudal tin forked. Anal 

 fin moderate. Ventrals under the dorsal, nearly median, of moderate length, rays to 14. 

 Pectorals placed low. A lateral line. Air bladder large. Stomach ctecal. Pyloric caica 

 few or none. 



ARGENTINA, Artedi. 



Argentina, Artedi, Genera Piscium, 8.— Cuvier, Rfegne Animal, 2tl eil., 1829, ii, 308. — Gill, Proc. Acad. 

 Nat. Sci. Phila., 1862, 15.— Gf'NTnER, Cat. Fish. Brit. Miis., vi, 202. 



Body fusiform, with mouth small; maxillaries and intermaxillaries short, the upper 

 jaw not reaching to vertical from anterior margin of orbit. Jaws toothless. Minute 

 teeth on head of vomer and on palatines in front. Tongue toothed. Ventrals behind dor- 

 sal. Caudal furcate. Branchiostegals well developed, C-8. Pyloric ca;ca present in mod- 

 erate numbers. Scales rather large. 



KEi' TO THE SPECIES OF ARGENTINA. 



A. Scales spinigerous. 



1. Body low (height 8 in total). Diameter of eye le.ss than or equal to snout A. sphyr^na 



2. Body high (5 to 51^ in height) . Diameter of eye greater than length of snout A. siLua 



B. Scales smooth. 



1. Body low. 



A. Diameter of eye greater than length of snont ; height of body 7 in total A. striata 



B. Diameter of eyeless than length of snout; height of body 8 in total X. elo.vgata 



ARGENTINA SPHYR.ENA, Linn.ecs. 



Sphyrtv.na parva, Rondeletius, Libri de Piscibus Mariuis, 1.554, I. 227. — Gesner, Fischbucli, 15,58, 88.3, KXil. 



Argentina, Willughbv, 1686. — Ray, 1713. — Artedi, 1738. 



Argentina sphyrcena, LinNjEUS, Syst. Nat., ed., xii, 1766, i, 513. — Risso, Ichth. Nice, 336. — ^Nilsson, Sliaud 



Faun., Fisk., 476. — Gunther, Cat. Fish. Brit. Mu8., vi, 203; Challenger Report, xxii, 218.— Canestrini,. 



Fauna d'ltalia, Pesci, 129.— Collett, Norges Fiske, 171; Forhandl. Vid. Sclsk. Christ., 1880, 92.- 

 Giolioli. Elonco, 102. 

 GonioKoma argentinum, Costa, Fauna Napolitaua, pi. xxxvi. 

 Osmerm hebridicm, Yarbell, Brit. Fish., 2d cd., ii, 133. 



