REPORT OF COMMISSIONER OF FISH AND FISHERIES. 39 
+ season a sinall number of herring eggs were secured and impregnated, 
these producing a small percentage of fry. 
On February 11, 1891, 200,000 lake trout eggs were received from the 
Northville Station, and produced 192,000 fry, which were liberated about 
the end of March, at points in the lake in the vicinity of the station. 
The collection of pike perch eggs was begun April 14, 1891, they too 
being taken by the fishermen; 149,000,000 eggs were obtained, of which 
58,000,000 were sent to the Erie hatchery of the Pennsylvania Fish Com- 
mission. In the collection of these Mr. William Buller, superintendent 
of the Erie hatchery, rendered active assistance. The eggs held at the 
station produced 60,000,000 fry, which were liberated in the lake prior 
to May 20, 1891, the season’s operations in fish-culture terminating with 
their release. Experiments were made with the pike perch eggs looking 
to the separation of those that mass in lumps. The method pursued con- 
sisted in detaching the lumps from the eggs already free, by means of 
ascreen. The lumps were then rubbed between the palms of the hands, 
separating the eggs. It was found that eges so treated hatched with 
no greater loss than those naturally free. Attempts to hatch the eggs 
when in lumps, however, resulted in almost total loss. 
NORTHVILLE STATION, MICHIGAN (FRANK N. CLark, SUPERINTENDENT). 
1889-90. 
Whitefish.—The collection of whitefish eges for this station was lim- 
ited to Lake Erie, 10,000,000 being derived from the vicinity of Monroe 
and 25,000,000 from Sandusky. These were carefully prepared for ship- 
ment and distributed to other hatcheries for hatching. The disposition 
of the good eggs, 28,460,000, is given in the details of distribution. 
The success heretofore attending the partial trial of graveled troughs, 
as practiced during the three preceding seasons in developing trout 
eggs, led to the adaptation of the method to all the trout eges handled 
at the station, and with results highly gratifying. This consisted in 
spreading as evenly as possible 10,000 to 12,000 eggs over a space of 
gravel bottom 12 by 15 inches. The eggs were allowed to remain on 
the gravel until the eye spots were clearly developed (a period of about 
forty days), being then taken up and placed on wire trays for hatching. 
Von Behr trout.—The readiness with which the Von Behr trout has 
become acclimated, together with its hardiness and rapid growth, has 
greatly encouraged its further propagation. From the brood stock 
163,400 eggs were obtained, of which 58,000 were transferred and 75,000 
held for hatching at the station. The spawning season began October 
21, 1889, and continued seventy-three days. From 75 females, 3 and 4 
years old, the production of eggs was 85,700, and from 239 females, 2 
years old, 77,700. Of this species brought over from the previous 
season, there were 6,175 yearlings delivered for distribution. 
