Johnson—Pyloric Caeca of the Centrarchidae. 715 
inadequate, however, to account for all the difference, which 
is considerable in Lepomis. 
Frequently a change in curvature in the caeca may be ob¬ 
served between caecum IV and caecum V, numbering the caeca 
from the gastric interval down the right side and up the left 
(the pollical caecum thus being caecum I). More rarely this 
change occurs between III and IV, or between V and VI. 
This change in curvature (Plate XLI, Fig. 3) is the result of 
the pressure of the pyloric portion of the stomach against the 
body wall. This forces the caeca to curve around the pyloric 
portion on each side. 
A branched caecum was found in three of 229 individuals 
(Plate XLIII, Figs. 2, 5 and 6). This is important, in view 
of the fact that another of the species examined, Micropterus 
salmoides, has its caeca normally branched. 
An average of twenty-one cases shows the longest caecum to 
be 15.0 per cent of the length of the fish. The length of the 
intestine from pylorus to anus is shown to be 1.14 times the 
length of the body in six cases. The length of the abdomen 
may be inferred by the length of the vent from the cephalic 
end of the fish. An average of eight cases showed this to be 
44.4 per cent. These figures are compared with those of the 
other species in Table I. 
Table I. 
Species. 
Length of 
longest 
caecum. 
Length of 
intestine. 
Length to 
vent. 
Lepomis pallidus. 
15.0 per cent 
13.2 per cent 
13.1 per cent 
15.2 per cen‘ 
1.14 
44.4 per cent 
47.5 per cent 
46.4 per cent 
40.0 per cent 
Ambloplites rupestris. 
1.02 
Eupomotis gibbosus. 
1.21 
Pomoxis sparoides. 
.62 
Ambloplites rupestris Fafinosque. 
Jordan and Evermann say of this species, “Caeca 7”. The 
specimens examined, however, showed a mode of 8 and a range 
of 6-9. It thus has the same range as the previous species, but 
with a mode one higher. The frequencies are shown and com¬ 
pared with the other species in Text-figure 1. The vari- 
44—S. & A. 
