378 
BULLETIN OF THE BUREAU OF FISHERIES 
BREEDING 
The fan-tailed darter spawns during the latter part of June and the first of July. 
Greeley (1927) found egg masses of this species in several places attached to the 
underside of flat stones in shallow water of moderate to swift current. There were 
about 400 eggs in a round mass, each one measuring individually about three-thirty- 
seconds inch in diameter. The young were one-fourth inch at hatching, with rather 
small yolk sac, and dark spots on the body. A male, probably the parent, was always 
found under the stone. The water temperature varied from 66° to 76° F. 
Family CENTRARCHID/E. Sunfishes 
48. Micropterus dolomieu Lacep5de. Smallmouth bass, black bass. 
RECORD OF CAPTURE 
Six larvse, 9.5 to 10 millimeters long, were taken on July 11 in a Helgoland trawl 
at 6 meters depth near Dunkirk, and others in a young-fish stage at the mouth of 
Eighteen Mile Creek on July 18, 1928. None was captured in 1929. Larvse and 
postlarvse were obtained for comparison and study from the Caledonia hatchery. 
The smallmouth bass is very abundant along the shores of Lake Erie, spawning in 
shallow places in spring and through the first week of July. 
DESCRIPTION 
This heavily pigmented, robust little fish with its bulbous head and large mouth, 
extending to the middle of pupil, will not be confused with other forms taken. 
Eggs . — Unfertilized eggs taken from the ovary of a 30-centimeter fish on June 29 
measured 1.2 to 2.52 millimeters in diameter, mostly 2.2. They were round, semi- 
transparent, light amber in color, with from six to many comparatively large, clear, 
dark amber oil globules (largest 0.9 millimeter). The eggs were not adherent, and 
only loosely joined together. 
8 .8 -millimeter stage . — Total length, 8.8; length to vent, 4.0; greatest depth, 1.8; 
diameter of eye, 0.85 millimeters. Myomeres, 10 before vent plus 19 behind (very 
incomplete). Embryonic marginal fin fold originating over end of yolk region, rising 
to slight elevation at position of later soft dorsal, similar on ventral side; caudal 
lophocercal; pectorals rounded. Head and yolk region robust, body compressed 
behind vent; eye large; mouth large, oblique, with maxillary extending to middle of 
pupil; intestine ending at edge of marginal fin. 
Pigmentation. — The whole larva is darkly spotted. Many large stellate chroma- 
tophores are massed over bulbous head, with fewer on sides of head and around jaws. 
