﻿53 91 



siderable dislance from the terminalion of the tube-like oesophagus; in some spe- 

 cimens tiicre is outwardly a slight constriction immediately in front of the place 

 where the biliary duct enters, which might seem to be the natural boundary for 

 the stomach; internally, however, no boundary can be seen, so Ihal this constric- 

 tion is probably quite accidental, produced by the contents of the inlesline. A true 

 pyloric constriction is likewise just as little developed here as in Amphisile, and 

 even if the part corresponding to the stomach is somewhat larger in Cenlriscus yet 

 it may be said that a true stomach is not developed here either. There is no 

 trace of appendices pyloricæ. The abdominal cavity is relatively shorter than 

 in Amphisile, and this is probably the reason for some small difference from the 

 latter form in regard to the position of the remaining part of the canal. Seen 

 from the left side (fig. 32) the position of the intestines is quite similar; thus the 

 small intestine runs backwards in the abdominal cavity, bends over in a sling 

 towards the right side and runs forwards almost as far as the entrance of the biliary 

 duct; here it bends upwards and again runs backwards a short distance, again 

 turns forwards in a sling round the spleen (/) then bends round again and runs 

 almost straight backwards to end at a distinct boundary in the rectum which is 

 here fairly long. Seen from the right side (fig. 33) the windings of the gut ditter 

 a good deal seemingly from the condition in Amphisile; more closely seen, however, 

 the difference is small; if the whole sling embracing the spleen is turned forwards, 

 we have exactly the same condition as in Amphisile. 



The contents of the intestine in 2 specimens I examined consisted of large 

 masses of Mysidæ, in a 3rd of Cumaceæ, Copepoda and small Annelids. 



The liver (h) has two main portions, a large left part divided into a larger, 

 lower and a smaller, upper lobe, and a small, undivided right part. The gall- 

 bladder (b) lies on the concave surface facing backwards where the right part 

 joins on to the common part connecting the lobes. 



In contrast to the condition in Amphisile the liver lies quite close behind the 

 heart (c) and the hepatic vein is thus exceedingly short. 



The heart (c) is also far removed from the ventral margin here and lies 

 obliquely with the bulb pointing forward and downward. The aorta lies on the 

 right side of the elongated vertebræ; it is accompanied by 2 cardinal veins, of 

 which the right is by far the larger. The large arteries to the pectoral fins are 

 given off from the aorta close behind the junction of the aortic roots, and the 

 A. coeliaca arises a little in front ventrally and somewhat to the right; the 

 A. coeliaca runs on the right side of the oesophagus and also further just as in 

 Amphisile; here also a branch is given off to the under side of the swim-bladder, 

 destined for the "rete mirabile". 



The venous system is in the main just as in Amphisile; but as already 

 mentioned the trunk for the vena hepatica is extremely short, in fact is not pre- 

 sent; it can be seen, however, that the branches from the lobes of the liver meet 

 in a common opening in the sinus venosus; quite close to this on the sinus venosus 



