632 



SCANDINAVIAN FISHES. 



ryngeals like l)ranchial arches, only shorter and thicker 

 than the ccratoliraiichial hones, and furnished with 

 three rows of teetli, the outermost consisting of caHii- 

 drical teeth, the middle row of pointed ones, l)Ut all 

 these teeth considerably shorter than those of the inner- 

 most row, which are larger, compressed, and ela^v-shaped. 

 Two of the three ujjper pharyngeals are thick and united 

 into one hone, which hears two I'ows of claw-sliapcd 

 teeth, at the l)ase hroad hut compressed, at tlie tip 

 sharply pointed. The skeleton of this species contaiits 

 7 abdominal and 10 cnudaj \ertebi'a', including the 

 urostyle. 



Within the subfamily of tlie BaJisthia-, <if wliich 

 about 30 species have been described, Bleekek esta- 

 blished 4 genera, differing in the form of the base 

 of tlie caudal tin and in tlie form and t'olour of the 

 jaw-teetli. Tlie foi'ms are so closely allied, however, 

 that a division into genera can lie defended onlv as an 

 expedient to facilitate a general survey of tlie subfamily. 



Among the peculiarities of the skeleton, besides 

 tliose mentioned above, the strong supporting apparatus 

 of tlie first dorsal tin, with the articulation of the first 

 spinous ray, which is the principal defensive weapon of 

 these fishes, is especially remarkable. The supporting 

 apparatus, which is evidently formed by the coalescence 

 and more advanced development of the elements of the 

 first interspinal bones, consists of three bones", the hind- 

 most of which is wand-like and lies in a backward and 

 downward direction, so that its hind extremity rests 

 against the lower part of the first interspinal bone of 

 the second dorsal fin — which bone is here supported 

 on the front of the ujiper spinous process (neural spine) 

 of the fifth abdominal vertebra — while the anterior 

 (uplier) extremit)' articulates firmly with the lower 

 end of tlie middle bone in the supporting apparatus. 

 This lione is triangular, with one angle directed down- 

 wards, but longitudinally cloven, its two wing-like 

 halves forming an angle open above and being firmly 



united in front and below to the first and largest bone 

 in the supporting ajjparatus. This last bone is canali- 

 c'ulate, but its long bottom is sliar])l\ i-irinated, thus 

 forming together with the middle bone w kind of boat, 

 with the bows pointing backwards and split (open) and 

 with a large, elliptical hole — crossed, however, by a 

 narrow, transverse bridge of bone — in the posterior 

 part of each side, l>ut with the middle of its stern 

 (turned forward in the fish) touching the middle ridge 

 of the cranium {sjiii/n oiii/iitalis) abo\c the liind part 

 of the orbits. The hind part of the gunwale (in the 

 fish the fore part) is furnished witli articular cavities, 

 one on each side, for the lateral articular processes of 

 the tii'st spinous ray, and from the middle of the bottom, 

 in tlie stern, rises a tap-like [irocess with rounded 

 head, over which glides the base of this rav, with 

 its concave centre. In front of this |irocess (i. e. 

 behind it in the longitudinal direction <jf the fish) rises 

 from the keel of tlie ho:it nnotlier taj)-like and round- 

 topj)ed process, o\er the head of which the cloven base 

 of the second s])inous rav glides to and tVo. The l)ack 

 of the first spinous ray is concave (canaliculate). The 

 front of the second spinous ray is tumid at the base, 

 and this swelling dro](s into the groove of the first spi- 

 nous vnv, when the ravs are erected. In this maimer 

 the first ra\- is locked fast, and am* attempt to force it 

 back mereh" exerts a pressure on the second rav, which 

 is thus kejit all the moi'c tirmh' fixed to its tap-like 

 articular process, and eft'ectualh- hinders anv liackwanl 

 curvature of the first rav. In order to attain this result 

 the second spiin)us ra\- must be drawn back, an opera- 

 tion which is jicrformed parth' by means of special 

 muscles, [lartly by a ligament which unites this ray 

 within the tin-meinl)rane to tlie third s])inous rav''. In 

 the MiiiKK <tntli'n}a\ which are without the third s])inous 

 ray, the supporting apparatus is also less developed; 

 and in the ']'ri(K-<iiitli'iii(f the first intt'rsjiinal bones are 

 only slighth' metamcn'|)liosed. 



" Cf. HoLi.AKD, .\nn. Sc. Natur., troisieme .serie, Zfiulug., toni. XX, p. 102; Sorensen, Om Li/dovgaiiev hos Fiske, p. 50. 



'' Hence, aecordirg to .Iounston {l)e Piscibus, p. 110), the generic name of Bnlistes (catapult). The Italians, he says, called one of 

 tliese fishes pesre balestra, because a slight pull at the third spinous ray was enough to overcome the rigidity of the first ray and to depress 

 it, just as a liglit touch of the hammer or trigger in the loclc of a cross-bow sufllced to discharge the weapon. This name reappears in tlie 

 English name of 7'riggcr-fishes as applied to these forms. Bah'stes was introduced into zoological nomenclature, without any special explana- 

 tion, by Artedi, first in Srba's Thesaurus, torn. 3, p. 63 and again iu Gen. Piscium, p. 53. 



