352 
BULLETIN OP THE BUREAU OP FISHERIES 
Family UMBRID./E, Mud minnows 
32. Umbra limi (Kirtland). Mud minnow. 
RECORD OF CAPTURE 
The mud minnow is sometimes found in weedy bays of Lake Erie, but is more 
common in the sluggish, weedy tributaries and near-by ponds. 
DESCRIPTION 
The mud minnow is most readily distinguished from the true minnows (Cypri- 
nidse) by its rounded caudal fin. 
24-75 millimeter stage. — Total length, 24.75; standard length, 20.5; length to vent 
14.0; length of head, 7.25; greatest depth, 4.75; eye, 2.0 millimeters. Cycloid scales 
in lateral line, 18 plus 17 = 35. Dorsal, 14; anal, 10 (rudimentary) spine before 
both dorsal and anal); pectorals very low, rounded, rather small; ventrals, 6, much 
posterior to pectorals, inserted very slightly before dorsal; caudal, rounded. Dis- 
tinguished by short, oblong body, rounded tail, and black bar at base of caudal. 
Mouth terminal, lower jaw slightly projecting; no lateral line. 
Pigmentation. — The body is well covered with very small gray chromatophores, 
except on ventral surface from behind head to vent. Top of head, dorsal ridge, and 
ventral ridge from vent to caudal are especially dark. A very dark spot occurs at 
base of caudal and all fins are marked. 
Family ESQCIOAZ, Pickerels 
33. Esox lucius Linnaeus. Pickerel, northern pike. [ Esox lucius americanus 
(Gmelin). Jordan, Evermann, Clark, p. 173.] 
RECORD OF CAPTURE 
The pickerel is not taken in Lake Erie except at the mouths of certain creeks, 
but is common in the larger streams among weeds. 
DESCRIPTION 
The pickerels will not be confused with other genera because of their ducklike 
snouts. The various species are distinguished chiefly by the degree of scaliness of 
cheeks and opercles, a criterion which can not be used in the identification of very 
young specimens. However, the dorsal ray and branchiostegal counts are sufficiently 
different to be used as distinguishing characters. 
Unfertilized egg. — Eggs stripped from a ripe female at Irving, N. Y., on April 8 
measured 2. 2-2.4 millimeters after expansion in water. Round, translucent, usually 
very slightly yellowish and often bright yellow. Surface covered with small colorless 
oil globules; yolk granular. 
Early development. — Ehrenbaum (1911) describes and figures the larval and post- 
larval stages of the same pike in European waters. There the larva is 9 to 10 milli- 
meters at hatching, with large yolk sac and inferior mouth. At 15 millimeters the 
lower jaw has begun to protrude, but the snout is very short. Tiny ventrals are 
apparent, but the wide marginal fin fold is intact. When the postlarva reaches 20 
millimeters the snout is considerably lengthened, the notochord turns definitely 
upward, and the marginal fin fold is persistent but deeply notched. At 26 milli- 
meters the permanent fins are formed and the young fish has a mature aspect. 
