ANATOMY OF B ALiEN OPTERA ROSTRATA. 
247 
A number of wide and rather shallow farrows ran from the cardiac orifice in a radi- 
ating manner over the wall of the cavity, passing towards its fundus, crossing but not 
interrupting the epithelial rugse just described. 
The orifice of the oesophagus measured in its transverse diameter about If inch ; it 
was thrown into plicae in the direction of the long axis of the tube, and presented a 
small valvular fold on the anterior border of the opening, which measured about f an 
inch in depth and rather more than f of an inch in length ; numerous pore-like orifices 
studded the entire epithelial surface, both on and between the above-described furrows. 
The aperture of communication between the first and second stomachs was defined by 
the sudden cessation of the cuticular lining of the former in a fringe-like border ; at this 
point the diameter of the viscus measured 3f inches. 
The second stomach was much larger than the first; it measured 27 inches in length 
and 22 inches in circumference, cylindrical in shape with rounded extremities, and in 
contour slightly sigmoid. The coats were much thinner and softer than those of the 
last-described cavity, their entire thickness being only f of an inch, and consisted of a 
peritoneal, circular, a fibrous, a submucous, which was very vascular, and an epithelial 
layer. The rugae on the mucous surface were much thinner, sharper, and more promi- 
nent than those in the first stomach, and towards the superior and posterior or concave 
margin they became very small, and interlacing with each other, produced quite a reti- 
culated appearance in this situation. The inferior border was thrown into transverse 
folds, about twenty in number, which ran in an antero-posterior direction parallel to 
each other ; each fold at its origin was small and flat above, but towards the convex 
edge it became large, thick, and prominent. These folds extended over the surface for 
about the length of 10 inches, with an average depth between them of 1 inch ; in the 
centre, at the distal extremity of the second stomach, these folds attained their greatest 
development, becoming smaller as they approached the orifice leading from the second 
to the first cavity. They were crossed by many smaller longitudinal rugae, which varied 
both in size and direction. 
The mucous membrane lining the orifice leading from the second to the third stomach 
was perfectly smooth; the opening measured 5 inches in circumference, and was 
surrounded by a well-defined muscular annulus or sphincter, whose free margin was 
mainly directed towards the cavity of the second stomach, and measured in depth about 
1 inch. 
The communication between the third and fourth stomachs was through a remarkably 
constricted oblique and valvular aperture which measured in circumference 5 inches ; it 
was guarded on the distal side, or that towards the fourth cavity, by a crescentic fold of 
mucous membrane which was very thin, and gradually shaded away on the wall of the 
cavity on both sides ; its extremities were about 1 inch apart, and its depth in the centre 
measured about 1-| inch. 
Within this orifice there was a pouch about 3|- inches long, 3 inches broad, and 3-^ 
inches deep ; it opened backwards into the third stomach by a large orifice, which was 
surrounded by a muscular annulus whose fibres were better marked below than above ; 
