Fishes of the Western North Atlantic 123 



Zool. Harv., 68, 1927: 239 (discus., mcas., Gulf of Maine) ; Breder, Field Bk. Mar. Fish. Atlant. Coast, 

 1929: 21 (general) ; Schroeder, Bull. Boston Soc. nat. Hist., 58, 193 1 : 3 (Gulf of Maine) ; Bigelow and 

 Schroeder, Canad. Atlant. Fauna, biol. Bd. Canad., iz', 1934: 13 (descr., distrib.) ; Vladykov and Mc- 

 Kenzie, Proc. N. S. Inst. Sci., rp, 193;: 47 (Nova Scotia); Bigelow and Schroeder, Bull. U.S. Bur. 

 Fish., 48, 1936: 322 (Grand Banks of Newfoundland); Fowler, Bull. Amer. Mus. nat. Hist., 70 (i), 

 1936: 32 (Italy). 



Lamna nasus Jordan, Copeia, 49, 1917: 87 (name); Hubbs, Copeia, 123, 1923: lOl (embryo. Gulf of 

 Maine); Jordan, Manual Vert. Anim. NE. U.S., 1929: 12 (general); Jordan, Evermann and Clark, 

 Rep. U.S. Comm. Fish. (1928), 2, 1930: 19 (distrib.) ; Piers, Proc. N. S. Inst. Sci., 18 (3), 1934: 202 

 (Nova Scotia). 



Lamna%^.{\) Gudger, Sci. Mon., N. Y., _?^, 1932: fig. 412, 413 (teeth). 



Isurus {Lamna) nasus Tonox\es&, Atti Soc. ital. Sci. nat., y^, 1938: 289 (small size, Medit.). 



Doubtful Reference: 



Lamna cornubica Lowe, Trans, zool. Soc. Lond., 2 (3), 1837: 194 (Madeira). ^^ 



Not Lamna functata DeKay, Zool. N. Y., 4, 1842: pi. 63, fig. 206, 207 (these ill. were evidently for /. 

 oxyrinchtis, see p. 131). 



Not Lamna functata Wilder, Science, i, 1880: 236 (Wilder's report of 10 embryos, in this case, makes it 

 likely that the reference was actually to some genus other than Isurus). 



Not Lamia nasus Lahille, An. Mus. nac. B. Aires, s4, 1928: 310 (the specimen in question seems in all prob- 

 ability to have been Isurus oxyrinchus, see p. I 30). 



Not Lamia nasus Vozzi and Bordale, An. Soc. cient. argent., 120, 1935: 150 (this reference is evidently to the 

 same specimen reported by Lahille, see above ; no doubt /. oxyrinchus) . 



Genus Isurus Rafinesque, 1 8 1 o 



Isurus Rafinesque, Carratt. Gen. Nuov. Sicil., 1810: II; type species, /. oxyrinchus Rafinesque, Sicily. 



Generic Synonyms: 



Oxyrhina L. Agassiz, Poiss. Foss.,^' Feuill. Addit., 1835: 71, 86; type species, "Lamna oxyrhina Cuvier anJ 



Valenciennes Mss.," equals Isurus oxyrinchus Rafinesque, I 8 10. 

 Oxyrrhina Bonaparte, Cat. Pesc. Europ., 1846: 17; type species, Oxyrhina gomphodon Miiller and Henle, 



I 841 , equals Isurus oxyrinchus Rafinesque, I 8 1 0. 

 Plectrosoma Gistel, Naturg. Tier., 1848: lO; to replace Oxyrhina L. Agassiz, 1835. 

 Isuropsis Gill, Ann. Lye. Nat. Hist. N. Y., I, 1862: 397; type species, Oxyrhina glaucus Miiller and Henle, 



1841. 



Generic Characters. Teeth without lateral denticles; the first 2 in each jaw noticeably 

 more slender and more flexuous than the others; origin of ist dorsal definitely posterior 

 to inner corner of pectoral when latter is laid back; trunk slender (Fig. 18) ; caudal fin 

 without secondary caudal keels. Characters otherwise as in Lamna (p. 1 1 1 ). 



Species. This genus includes: the "Sharp-nosed Mackerel Shark" or "Mako" of the 

 Atlantic (/. oxyrinchus, p. 124) ; the closely allied Pacific Mako (/. glaucus), with which 

 bideni-'' from South Africa and mako'^ from New Zealand and Australia appear to be 



25. Being nominal only, and from a region where oxyrinchus is to be expected, there is no way of knowing to 

 which species this record actually referred. 



26. For dates of publication of the separate parts of the "Poissons Fossiles," see Jeannet (Bull. Soc. neuchatel. Sci. 

 nat., 52, 1928: 102; 53, 1929; 197). 



27. Phillipps, N. Z. J. Sci. Tech., 7j, 1932; 227. 28. Whitley, Rec. Aust. Mus., 77, 1929 : loi. 



