703 



Fam. COBlTIDiE. 



Air-bl(uhliy more or less rednced, oitirclf/ or jKirth/ enclosed in an osseous capsuJe. 3[oidli fringed ivith six or 



more hiirlx-ls. I'sendohraneliiic nrintini/. 



This faniily was established under tlie name g\\en 

 above by Boxai'aktk" in 1S46, but subsequently re- 

 ceived of Meckel and Kneu'' the name of Acanthopsi- 

 des, derived from the generic title which Agassiz had 

 suppiiseil to be deserved by our most common species. 

 By most authors, however, the family has been regarded 

 as a snbfamilv among tlie Cyprinoids. Still it possesses 

 so nianv distinctive cliaractcrs tliat it may well main- 

 tain its jiosition in the system. The most iirominent 

 among tliesc cliaractcrs are tliose wliicli suggest an 

 alliance with the Glanomorph series. Among these we 

 tind externally the slim)* skin, generally naked, other- 

 wise witli small scales, and the comparatively numerous 

 barl)cls niuiid the mouth; while internally the capsule 

 of the air-bladder reminds us of tlie corresponding 

 structure in many of the Glanomorphs, and the ossifica- 

 tion of the head shows a fronto-parietal fontanel simi- 

 lar to tliat we liave remarked above in the Siluroids. 

 The intestinal respiration of the Cobitoids may also 

 be in some degree a trace of tlicir connexion with the 

 preceding series of forms, ^vhere \ve have seen the 

 resi)iration of air accomplished in various ways, and 

 where the respiration of water seems in certain fishes 

 to be assisted by an apparatus consisting of ramified 

 appendages in the anal region. In the present series, 

 on tiie other hand, it has long' been kno\vn tliat under 

 certain circumstances, where there is scarcity of water 

 or of the oxygen contained therein, our European Co- 

 bitoids ascend to the surface and swallow air, which 

 they audibly eject after a time thi-ough tlie vent, with 

 the oxygen now changed to carbonic acid gas. 



Tlie Coliitoids are distinguished from the following 

 family not only by the capsulate air-bladder and the 

 greater number of the barbels, but also bj' the absence 

 of pseudobrancliia' — this is also the case in the great 



braiies being united underneath for the greater portion 

 of their length to the istlimus. The lower pharyngeals 

 are destitute of the .strength ^\■hich they possess in the 

 following family, are more like branchial arches, and 

 are armed witli a row of weaker, but in general more 

 numerous teeth. 



The air-bladder is partly free, it is true, in several 

 fishes of this family, a posterior division thereof lying 

 free within the abdominal cavity. But in others, and 

 in particular in all our ICuropeaii species, it is com- 

 pletelj' enclosed in a jwrous or retiform, osseous cap- 

 sule, or only a small, rounded expansion of the air- 

 bladder'' juts out at the hind orifice of the capsule, 

 where otherwise only the pneumatic duct descends to 

 the a'sophagus. The osseous capsule of one of the 

 European species, Cohitis {Misgurnus) fossUis, is excel- 

 lently described and figured by Weber (1. c). Its 

 morphological explanation consists in a tumidity and 

 transformation of the osseous structure originally be- 

 longing to the lower and inner parts of the transverse 

 processes of the third vertebra and to its pair of ribs. 

 The upper and outer (dorsal) part of this transverse 

 process on each side may still lie distinguished in the 

 wall of the capsule; and in our Spined Loach (Cohitis 

 tcenia) the top of this process, as well as each of the 

 ribs behind it, bears a scleral (epipleural, muscular) 

 bone branched at the top. The osseous point that pro- 

 jects downwards on each side of the capsule, also pre- 

 sents an unmistakable resemblance to the ends of the 

 ribs behind this point. The same explanation is given 

 of the hollow bone extending from each side of the 

 body of the second vertebra and from the lower part 

 of its neural arch, backwards, outwards, and down- 

 Avards, above the anterior ujiper part of the surface of 

 the osseous capsule. Within this hollow btme are con- 



majority of the (ilanomorphs — and the comparatively , taiiied the so-called acoustic bones. In the Spined Loach 

 small size of the gill-ojienings, the branchiostegal mem- this hollow l)one — the outcome of the material of the 



" Cat. Met. I'esc. Europ. pp. 5 and 26. 



' Siisswasserf. Oesterr. Mon., p. 296. 



' See Erman i Gilbert's Aiinalen der Physik, Bd. XXX (U 



■' See Weber, De Aure etc., tab. VI, fig. 48, sign. 8. 



140. Cf. also SiEBOLD, StisKwasserf. Mitteleur., p. 340. 



