704 



SC A N I ) I X A V 1 A N I- 1 S 1 1 1 . S . 



lateral parts uf the second vertebra — hears on its top 

 a scleral bone, the second in order iVoiii in tVont: — 

 the first (sometimes double) lies on eacli of the lateral 

 occipital bones. 



Such is the osseous capsule in Cohitls fossiUs and 

 C. tfenia, in form a transversely-set ellipsoid, entire, and 

 contracted only at the njiddle of its ventral side by a 

 shallow groove in the longitudinal direction of the body; 

 but in our second species, the Loach {Cobitis harhutuhi), 

 this contraction has gone so far that the two lateral 

 parts of the osseous capsule are separated from each 

 other, though posteriorly united on the ventral side by 

 a hollow osseous bi'idge. In this species we also find, 

 strange to say, a well-developed pair of ribs on the 

 tirst vertebra. 



On each outer (lateral) side of the osseous capsule 

 (or on the outside of its divisions in the Loach) we 

 find two holes, one of which leaves room for the union 

 of the hind extremity of the so-called malleus with the 

 air-bladder, while the second, posterior, and larger hole 

 admits into the osseous capsule, to the lymphatic cham- 

 ber surrounding the air-bladder", a membranous duct 

 from the subcutaneous connective tissue. A communi- 

 cation {introitus capsuJce vesica) is thus formed between 

 the aii'-bladder and the side of the body exactly above 

 the insertion of the pectoral fin and on a level with 

 the upper angle of the gill-opening', where this duct 

 passes between the dorsal and lateral divisions of the 

 gi'eat lateral muscle. The latter communication has its 

 analogue, as ^ve have seen above, both in Balistes and 

 the Glanomorphs; but here we have no evidence to 

 show that it is connected in any way with the pro- 

 duction of sound. On the other hand, the signification 

 which Hasse and Sagemehl have attributed to the con- 

 nexion between the air-bladder and the apparatus of 

 hearing, that of a barometrical apparatus, here finds 

 perhaps its strongest corroboration, for we know that 

 these fishes are so sensitive to changes of atmospheric 

 pressure that they have long been ti-usted as weather- 



pro])hets. One species (J//.s7/*o-««s /o.s-.s77/.s-) has received 

 in (iermany the name of Wetterjisch'. "It has been 

 observed," says Blocu' '"that at the ap])roach of storm 

 this fish rises from the Ijottom towards the surface and 

 is particularly restless in its movements. It may there- 

 fore be used instead of a weather-glass, if set in a glass 

 vessel containing river-water (jr rainwater and a little 

 rich soil at the bottom. Twenty-four hours before a 

 storm of Avind or thunder it invariably grows restless, 

 disturbs the water till it becomes turbid, and rises and 

 sinks up and down in the vessel. In settled weather, 

 on the other hand, it usually lies still at the bottom. 

 The fish may be kept alive almost a whole year, if 

 the water and soil are changed only twice throughout 

 the summer and once a Aveek during the winter. In 

 winter, however, it must be placed in a warm room 

 and at a- window." 



The Cobitoid family consists exclusively of fresh- 

 water fishes, the great majority belonging to Asia and 

 the neighboui'ing islands. According to Bleekei! the 

 number of species exceeds 80; Day knew 46 from In- 

 dia. The former distributes these species among 12 

 genera, Gunther" I'ecognises 11. The three species that 

 occur in Europe belong, according to these opinions, 

 each to a distinct genus, the first {MisgiiniHs) with bar- 

 bels on both jaws — this character is possessed by 3Iis- 

 ffurniis fossiUs, an inhabitant of the regions south and 

 east of the Baltic — , the second genus {Nemachilus) 

 without erectile spine below the eyes (like Misf/iirnus), 

 but without barbels on the lower jaw — this genus is 

 represented by the Loach (NemaehUus harhatuhis), which 

 has been observed in several localities in Scandinavia — , 

 and the third (Cobitis) containing our common Spined 

 Loach {Colli f is fceiiia), without barbels on the lower 

 jaw, but with an erectile spine (at other times directed 

 back^vards) below each eye. It has already been re- 

 marked, however, by Valenciennes-' that on a very 

 niiiuite examination of Misjiurnus fossiUs we discover 

 a small crevice in the skin below each eye, and that 



" Cf. Hasse, Anatomische UStuiUen, Bd. 1, p. 595. 



* See Webeb, 1. e., tab. VI, figg. 45 and 46. 



' Heokei, and Kneb. Siisswasserf. Oesterr. Man., p. 300. 



■^ Nnturg. Fisch. Deulschl., Th. I, p. 218. 



■■ Iittrod. ^ti(d. Fish., p. 604. 



■^ Cuv., V.\L., Hist. Nut. Poiss., v«]. XV'III, p. 6. In our spociinens of Misgnrnus fossiUs we easily discover a longitudinal groove helow 

 the eyes; but tlie crevice in the skin is impossible to detect, and the spine that may be felt at the lower anterior corner of the eye, lies 

 in front of the said groove. On dissection, however, it appeared that Weber {De Aure etc., figs. 43 and 44) was perfectly correct in re- 

 presenting in his figure a preorbital spine in Misgurrms fossiUs. This spine lies hidden among the muscles, but is movable as in Cobitis 

 tania and has the same form, the analogy being so complete that the other spine, whicli is more easily felt externally, corresponds to the 

 lateral spine on the true preorbital spine of Cobitis tarda. 



