moodie: cretaceous fishes. 279 



scribed. Cope (ISa) figured an incomplete one and Hay men- 

 tioned another. Hay (11) has figured a portion of the caudal 

 fin of an Empo showing the extreme character of segmenta- 

 tion of the rays. The same character is shown in the pectoral 

 fin. 



The stomach is rounded, somewhat laterally compressed, 

 and elongate in a shghtly U-shaped curve. There are eight 

 muscular constrictions on the ventral surface and four on the 

 dorsal. The constrictions, on the ventral surface, occur in 

 groups. Anteriorly there are two close together. This group 

 is separated by a space of an inch and a quarter from the next 

 group, in which there are three, which occur a little over one- 

 half inch apart. The last group, also of three, is separated from 

 the second group by one inch. The surface of the stomach 

 cast is covered with a dark, apparently carbonaceous, ma- 

 terial which may be carbonized muscle, together with a few 

 large scales of the typical Empo form. Running the entire 

 length of the specimen are longitudinal ridges and grooves 

 showing the cast of the muscular walls of the stomach. 



The interior of the stomach, in cross section, shows no food 

 material, but only chalk. It is possible that the fish, like some 

 of its modern relatives, may have been a bottom feeder and its 

 stomach may have been partly filled with Niobrara mud at the 

 time of its death. There must, however, have been some sedi- 

 ment enter the stomach after death, for the full form of the 

 organ is preserved as though the entire stomach cavity had 

 been packed with mud. Furthermore, the form of the stomach 

 is that of a carnivorous fish, and recalls very strongly the 

 stomach of a mountain trout or of the sunfishes of our inland 

 streams, all carnivorous in habit. 



The portion of the alimentary canal preserved is in two 

 lobes. The first lobe is undoubtedly the stomach proper, and 

 the constriction between the lobes is the pyloric region. The 

 other lobe is unlike anything among modern fishes with which 

 I am at present acquainted. It is undoubtedly an enlargement 

 of the intestine and possibly served as a secondary stomach. 

 It lacks the muscular constriction and the longitudinal plicse. 

 The plicse are, however, continued well across the pyloric 

 region to the beginning of this second enlargement. 



The pectoral fin, as preserved, is well characterized in the 

 photograph (plate LXII, figure 2). It is somewhat turned in- 



