108 



SCANDINAVIAN FISHES. 



THE FRIGATE-MACKEREL OR PLAIN BONITO. 



AUXIS THAZARD. 



Fig. 31. 



Hack (/Idssi/ iiidit/o or (jrai/ish blue, frith irregular, dark-blue spots and stripes, u-Jiieli sometimes ranisJi: ventral 



sides silvery. 



Fig. 31. Fiigatt-Maclierel (Atixis tliazard), from tlie soutli of tlie Cattegat. Specimen belonging to Lund Mupunnj. '^ natural size. 



R. bi: 7; /'. 10 

 r. 22 1. 23; V. '/-; C." ,c+19+^ 



11/— — /VIII 

 '9 1. lO' 



IX; A. 



10 1. ll' 



6'i/n. tScuiiiher tluizard, Lacep., Hist. Nat. Poiss., vol. Ill, p. 9; 



Cuv., Val. {Aiixis = Scomber ta:o, Commerson), ///.</. Nat. 



Poiss., vol. VIII, p. 146; Br.-Goode {Au.vis), Fish. Indnstr. 



U. S., part. 1, p. 305, tab. 92. 

 Scomber Boclici, Risso, Ichth. Nice, p. 10.5; Id. ('/'ki/ninis 



rocheantis), Eur. Mer., vol. 3, p. 417; Gthr, (Auxis), 



Cat. Brit. Mus., Fish., vol. II, p. 369; Nilss., Ofvers. 



Vet.-Akad. Forh. 1863, p. 500, tab. VI, Day, Fish. G:t 



Brit. Ircl., part. I, p, 104, tab. XXXIX, fig. 1 et 1 a\ 



LiLLJ., Sv., Norg. Fiskar, vol. I, p. 280. 

 Scomber bisiis, Rafin., Caratt., p. 46, tab. 2, fig. 1. 

 Aii.vis vitli/aris, Cuv., Val., 1. c, p. 139, tab. 211. 

 Orcynus thynnus, Br.-Goode, Fish. Industr., I. c, tab. 96. 



Olis. Though CuviRE distinguished between Commerson's Scomber 

 taso and the Frigate-Mackerel described by Risso and Rafinesquk, he per- 

 sonally acknowledged that he could discover no other difference than 

 the absence in taso of the dark markings on the back, which he 

 sometimes, liowever, could not find in the Frigate-Mackerel (1. c, p. 

 145), and a small, uval, blue-black spot under the eye, which, on 

 the contrary, he assumed to mark taso. Both Day and Brown-Goode, 

 however, have amalgamated the two species; and, as we already know 

 from GUnther's explanation of Bleekeu's Auxis thynnoides as a syno- 

 nym for A)i.ris Nochei that the Frig.ite-Mackerel has a place in the 

 fauna of the East Indian Archipelago, there should be no doubt as 



to the meaning of LACEpiiDE's Scomber thazard, a name which we 

 must thus recognise as the original designation of the species. 



The form of body of the Frigate-Mackerel changes 

 so much with age tliat we have iu it an admirable 

 example of the transition from the Mackerel-type to 

 that of the Tunny. During youth the greatest depth 

 of the body is not more than \'j; of the length; luit 

 in old specimens it rises as high as ^/^. With respect to 

 the great distance between the two doi'sal tins, whicli may 

 be more than twice the length of the base of the first 

 dorsal, the Frigate-Mackerel, as ^ve have already stated, 

 is really a Mackerel; but by the situation of the second 

 dorsal fin, Avhich lies either completely, or for the grea- 

 ter part, in front of the perpendicular from the begin- 

 ning of the anal, it ranges itself with the Tunnies. 



According to Nii.sson's measurements the situa- 

 tions of these tliree fins are as follows: 



Distance between the first dor.-;al and the tip of tlie snout in '« of 



the length of the body, 32.8; 

 Distance between the second dorsal and llie lip of the snout in °o of 



the length of the body, 68.2; 

 Distance between the anal and tlie tip .of tiie snout in "i of tlie 



length of the body, 74.1. 



" .r -r 2 1 -f- .(■ according to MouEAU. .r -(- 1 4 -F .c according to LlI.IJEBORG. 



'' Bi.eekek's Auxis tajicinosoma. from .Japan is also, according to STEiNPAniXKi! (Dcnksclir. Matli. Naturw. CI. AUad. Wiss. Wien, Bd. 

 XLIX, p. 180), identical witli .-Ik.W.v Hochei. 



