DISCUSSION OF SPECIES AND THEIR DISTKIBUTION. 51 



PTEROTHRISSUS, Hilgendorf. 



Pterothrissus, Hilgemdorf, Act. Soc. Leopoklina Carol., xiii, Nos. 15, 16, September 3, 1877, 127.— Sitz- 



uussber. Naturf. Frcunde, 1878, 156 ; 1887, 187. 

 Balhythriisa, GuNTHER, Ann. ami Mag. Nat. Hi8t.,xx, 1877 (November 1), 433.— Challenger Report, XXII, 220. 



"Body covered with scales of moderate size; head narrow, obloug, with mucilerous chan- 

 nels much developed. Bye lilir,>^•(^ Mouth narrow, coregonoid, with bands of minute teeth 

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

 forked, with a dense layer of small scales. Air bladder with very thick walls, terminating 

 in two .short horns in front, iiointed behind." {Giinther.) 



Pterotlirissm was published September 3, 1877, and Bathythrissa, November 1, 1877. 

 (See Sitzungsbericlite, Naturf or schende Freunde, 1887, No. 9, 187, 188.) 



The genns and family are known only from a single species, P. f/issn, Hilgendorf 

 (Figure 52) [ — Bathythrissa dorsalis, Giinther, Challenger Eeport, xsii, 222, pi. lvi, tig. AJ, 

 from Japan taken in 315 ( ?) fathoms. 



Family ARGENTINID.^. 



Argentinina, Jordan and Gilbert, Bull, xvi, U. S. Nat. Mus., 1883, 288. 

 Argentinidce, Gill, Smithsonian Report, 1884, 619. Jordan, Cat. Fi.sh. N. A., 1885, 42. 



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

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

 maxiUaries not protractile. Teeth in jaws absent. Four gills, a slit behind the last. Pseu 

 dobranchiic present. Gill membranes separate, free from the isthmns. Branchiostegals 

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

 fin moderate. Ventrals nuder the dorsal, nearly median, of moderate length, rays 9 to 14. 

 Pectorals placed low. A lateral line. Air bladder large. Stomach ca;cal. Pyloric ca;ca 

 few or none. 



ARGENTINA, Artedi. 



Argentina, Artedi, Genera Piscium, 8.— Cuvier, Rfegne Animal, 2d ed., 1829, ii, 308. — Gill, Proe. Acad. 

 Nat. Sci. Phila., 1862, 15.— Gunther, Cat. Fish. Brit. Mus., 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 cceca present iu mod- 

 erate numbers. Scales rather large. 



KEV TO THE SPECIES OF ARGENTINA. 



A. Scales spinigerons. 



1. Body low (height 8 in total). Diameter of eye less than or equal to snout A. SPHTRiENA 



2. Body high (5 to 5+ in height). Diameter of eye greater than length of .snout A. siLUS 



B. Scale.s smooth. 



1. Body low. 



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



B. Diameter of eye less than length of snout; .height of body 8 in total A. elongata 



ARGENTINA SPHYR^NA, Linn^us. 



Sphijrana pnrrn, Rondei.etics, Libri de Piscibus Marinis, 1554, i. 227.— Gesner, Fischbuch, 1558, 883, 1061. 



Argentina, WiLLUGHBY, 1686.— Kav, 1713.— Artedi, 1738. 



Argentina sphyrwna, Linn.eus, Syst. Nat., ed., xii, 1766, i, 513.— Rlsso, Ichth. Nice, 336.— Nilsson, Skand 



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



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

 GiGLiOLl, Elenco, 102. 

 Goniosoma argentinum, Costa, Fauna Napolitana, pi. xxxvi. 

 Osmcrits hcbridiciis, Yarrell, Brit. Fish., 2d ed., ii, 133. 



