CAVE FISHES OF NORTH AMERICA. 383 
branes joined to the isthmus, sometimes loosely; body covered with 
very small, irregularly arranged cycloid scales; no lateral line; vent 
in the young located in the normal position, but in the adult far for- 
Cut 8.—Internal anatomy of Amblyopsis speleus. 1, anus; 2, opening of the oviduct; 3, oviduct; 
4, ovary, which is single; 5, liver; 6, duodenum; 7, gall-sac; 8, pectoral fin; 9, one of the pyloric 
coeca; 10, cecum; 11, stomach; 12, spleen; 18, air-bladder; l4and 16, intestine; 15, pancreas; L, liver. 
ward, just behind the angle of the union of the gill membranes. The 
transition of the vent from what_is its usual position in most fishes to 
this unusual one just back of the gill openings takes place gradually 
as the fish matures”; ventral fins wanting 
except in Amblyopsis, very small in this 
species; pectorals inserted rather high, mod- 
erate in size; no spines in any of the fins; 
dorsal and anal fins nearly opposite; caudal 
rounded or even pointed at the tip; no as 
median crest on the cranium; stomach ccecal, x 
with 2 to 4 pyloric cceca; air-bladder well de- ©" aa cas Neer eter eae 
veloped; ovary always single. Eggs caught 
by the gills when spawned, at least in Amblyopsis, and held there 
until hatched; young remain in the gills in Amblyopsis until about 
four-tenths of an inch long.? 
a@Ina specimen of Amblyopsis 1.26 inches long the anus is just below the insertion 
of the pectorals. In a specimen 1 inch long it is nearer the ventrals than the pec- 
torals. Inaspecimen of Typhlichthys 1.1 inch long the anus is well in front of the 
pectorals, but a short distance behind the gill.—Kigenmann, Pop. Sci. Mo., LVI, 
1900, 485. 
bigenmann, Marine Biological Lectures, 1899, 318. 
