REPORT OF COMMISSIONER OF FISH AND FISHERIES. 85 
_ Fry.—All eggs were hatched in April and the fry were in good condi- 
tion, except Atlantic salmon, and the parentage of this lot is mentioned 
-under the heading of Green Lake Station. In order to accommodate 
,and successfully care for the young fish in process of rearing, it was 
‘necessary to erect, in advance of more permanent constructions, a 
‘temporary outdoor stand containing 46 troughs. These, with 38 half 
-hogsheads, arranged at the same point, and the interior troughs of the 
‘hatchery, afforded 126 receptacles. The supply conduit, 7,050 feet 
Jong, was ventilated by the removal of boards at more than 300 points, 
and for still more complete aération 25 breakwaters were inserted. The 
‘flow was increased to permit the employment of 15 to 25 gallons of 
| water per minute to each trough and tub. Four temporary ponds, to 
‘receive the waste of outdoor receptacles, were among the preparations. 
Supplies of food, consisting principally of liver, were obtained at 
| Bangor instead of Ellsworth at a reduced rate of cost. The older fry 
‘began feeding May 12, all others following before the end of the month. 
The approximate stock of fry May 31, with losses, is given below: 
Percent- 
Kind. ea Discarded. age of 
Oss. 
MPERIEM GI CCH TNO a= seicia ha cinis\alo el aicis sian'cis aie wise eiaie ws miuelale stcieim etaisiaierete le 164, 000 5, 937 3.4 
MITA OTLU) ota aici esate eeisas se ieieiselbisjmn site me esnfein Rieke oie e alate mists o:2faje a apelin 6, 000 555 8.4 
BIPISG HT UNOUb sacs ais mae). ane mcacs ccs cine ioc ticie cts genie aeiristle sale ass 49, 000 1, 412 2.8 
EMPIRE ONG ee esata fo ons Aaa Saara, 2 fei emelaatho «2 tna omental 4 46, 000 2, 521 Sul 
MPIC CI ULOU Gas sc aeiae cacmcenic ac tonic aiaciec secon encinste rele meee ai sz 29, 000 736 27 
MEATEROMS ALIN GTi ae serciacte te neies we plas tare eins Oe Seth ale Dajaiurs, b vetelslnlalsi crate kalo s 8, 000 4, 389 35 
The only material loss during June was through the instrumentality 
of a parasite which attacked and destroyed the greater portion of the 
| lake trout and a relatively smaller number of-salmon. <A report on 
this subject, by S. G. Worth, contained the following: 
The lake-trout fry in rearing-troughs, both outdoors and under shelter, were under- 
going a higher rate of mortality than any other species, their bodies being dotted 
with white spots. It had been found that the treatment with salt, termed ‘‘salt- 
' ing,” had lowered the death rate, practically ending it, but no solution of the malady 
"was given. My examination showed that the spots on an average were the size of a 
- common fly speck, scattered irregularly over the bodies of the fish, on the foreheads, 
| sides, tail, and fin bases, and even on the extremities of these appendages. The 
spots were white with a tinge of blue, the blue being due, perhaps, to sky reflection. 
' They were easily removed by a knife blade and came off immediately on contact with 
cheesecloth hand-net. 
The fish had been feeding poorly and at first I thought the spots were pimples 
resulting from intestinal inflammation—in other words, an eruption. This surmise 
was strengthened by the limp consistency of the pimples, some of which were 
pointed at their apexes, the general appearance being that of mucus. Upon detach- 
ing specimens they had the appearance of clabber (sour milk), and under a pocket 
glass of low power I found irregular watery markings, occupying, in some specimens, 
25 per cent of the area. Upon examining them patiently I discovered a movement 
in one and later in another, and finally seven specimens on the pane of glass, as 
if recovering from the shock incident to detachment, were all in motion, circling 
around at the rate of one-eighth to one-fourth inch per second. Hence I inferred . 
that the spots were animals, parasites, perhaps the larve of some insect. 
> 
