of graminivorous and carnivorous Animals. 161 
immediately beyond the pylorus, where the duct of the liver 
opens, the duodenum has a different structure. Vide Plate 
XIII. fig. 1. 
XXIII. The Turtle. 
The stomach is a continuation of the oesophagus, and begins 
where the projecting papillae of that canal terminate. The car- 
diac portion is of an oval form, has a rugous internal surface, 
but no distinct glands were observed ; it communicates with, 
the pyloric by a small orifice ; the pyloric is bent upwards 
and retained in that situation by the mesogaster ; its coats are 
very thick, and their substance contains many small glands with 
ducts leading into its cavity. Vide Plate XIII. fig. 2. 
XXIV. The Frog. 
The stomach is in its general characters like that of the 
turtle, but on a very small scale, and no particular glandular 
structures were distinguished. Vide Plate XIII. fig. 3. 
XXV. The Blue Shark. 
The oesophagus is three inches long, and lined with a cuticle. 
The cardiac portion of the stomach is 18 inches long and 8 in 
diameter ; it communicates with the pyloric by an orifice of 
an inch in diameter. The pyloric portion is 18 inches long 
and one inch in diameter. The fish was 7 feet 5 inches long. 
The internal membrane of the cardiac portion is rugous, 
and orifices leading to glands are seen upon it. That of the 
pyloric portion is smooth. Beyond the pylorus there is an 
enlargement where the intestine begins, and into this cavity 
the duct of the liver opens. Beyond this the spiral valve of 
