28 CLASS XIV. 



secretion by two ducts close to the duct of tlie gall-bladder \ In 

 Cyprinus E. H. Weber had found a duct close to the" ductus 

 choledoclius, opening into the intestine, and dividing into branches 

 in the liver, but containing no bile\ Since however in the in- 

 vestigation of fishes that have aj)pendices ])ylor{c(B a distinct pan- 

 creas has lately been discovered in addition^, it would seem that 

 the opinion which assigns to these appendages the place of this 

 gland can no longer be maintained ; probably, however, they also 

 secrete a fluid that assists in the conversion of the food; for that 

 they merely supply the intestine with a larger surface for absorp- 

 tion, at least where they are closely collected into bundles or divided 

 into branches, is not easily to be imagined*. In Lepidosiren the 

 appendices jyylor km and \\\Q pancreas are wanting. 



Fishes have a large, soft liver, saturated, as it were, with oily 

 fluid. It often extends far backward in the abdominal cavity, and 

 sometimes fills the spaces between the convolutions of the intestinal 

 canal, as in the molluscs. In many fishes it lies more to the left 

 than the right side. Its form is very various ; when it is divided 

 into lobes the number of these is very different, mostly, however, 

 two, which are united by a small strip. In Myxine the liver 

 consists of two portions quite distinct from each other. The gall- 

 bladder is absent in very few species only of fishes ; commonly it 

 is large. Its duct, or the gall-bladder itself, receives the hepatic 

 duct from the liver and penetrates the intestinal canal mostly close to 

 the pylorus. The venous blood of the intestines is carried by three 

 or two trunks, or by a single larger trunk, and usually by smaller 

 branches in addition, to the liver. The venous blood from the 

 swimming bladder, and in some fishes that also which returns from 

 the organs of propagation, also flows to the liver before returning to 

 the heart ^. 



nnt. anat. Coll. x>r hat. Amstel. II. p. 35, Tab. viii. fig. i; F. G. Mieeen- 

 DORFF De Uepate piscium. Berolini, 181 7, Svo, p. 50, fig. 1. 



2 Meckel's Archivf. Anat. u. Physiol. 1827, s. -294 — 299, Tab. iv. fig. 22. 



^ In Acipenser Sturio by Alessandrini, Ann. des Sc. nat. Tom. xxix. 1833, pp. 193, 

 194, and lately by Stannius, in many fishes of different families. Mueller's Archiv, 

 1848, s. 405—407. 



•* "Very rarely, if ever, has chyme been found in the appendages. 



s Compare on the liver of fishes, besides the work of Mierendorpf cited above, 

 H. Eathke in Meckel's Archiv f. Anat. u. Physiol. 1826, s. 126 — 152, and in 

 Mueller's .A ?'cAn', 1837, s. 468 — 475. 



