MARINE BIOLOGICAL STATION AT PORT ERIN. 41 
measuring 10x 51x83 feel. On the left side of the west 
door are three shallow wooden tanks, 4x2 x1 feet, used 
for the storage of the mussels for feeding the fish. There 
is a circulation of sea-water through all of these tanks. 
The series of eight hatching tanks, arranged in pairs, 
with passages between adjacent pairs, occupies the north 
side of the room (see fig. 7). Each tank, of wood 1 inch 
thick, measures 7 feet 7 inches long by 2 feet 34 inches 
wide and, over all, is 11 inches deep. It is divided into 
fourteen compartments, of which those at the ends are 44 x 
127 inches, with a semi-circular opening at the bottom of 
the partition. The other compartments measure 154 x 121 
inches: all are the same depth. At the centre of each 
end of each compartment is a shoot, made of sheet brass, 
*z Inches wide, § inch deep and 14 inches long, to lead 
the running sea-water from one compartment to the next. 
Down the middle of each tank runs an iron bar (OB in 
fig. 3), 1 feet 65 inches long, 14 inch deep and 2 inch thick. 
One end is hinged to the upper end of the tank, the other 
is free, and the bar is pierced at five points, measuring 
trom hinge 153, 311, 471, 
and into these holes are fixed short transverse iron rods 
(13 QB) = 5 AVANG! she, 
602 and 782 inches respectively, 
g inch thick and 32 inches long. The bar carries two leaden 
weights, of 34 Ibs. each, grooved so as to slide at the free 
end. The bar in working up and down (see fig. 3, Gd) is 
guided by an iron, 1 inch wide 8 incnes long, shaped like 
a tuning fork and fixed 18! inches from the lower end of 
the tank. The inside of the tank is coated with a mixture 
of tar and pitch, applied hot. Each tank rests on three 
trestles and is 22 inches above the floor at the upper end 
and 192 inches at the lower one. 
Hach of the ten larger compartments in a hatching 
tank contains a hatching box made of wood % inch thick 
and measuring 121} x 111x923 inches. The bottom is made 
