110 TRANSACTIONS OF THE ROYAL CANADIAN INSTITUTE. [VOL. X 
to test his watchfulness. Since that time the dip net has received many 
a jerk for a similar reason when it has been poked among the rocks in 
collecting. When the tide is low and the surface of the water is smooth, 
it is an easy matter in certain localities to see several of these fish on 
duty, as the opaque whiteness of the mass of eggs makes discovery an 
easy matter. 
In the vicinity of Nanaimo spawning takes place during the latter 
part of January or early in February. The eggs, about 2.8 mm. in 
diameter, differ from the eggs of many other species in that they are so 
opaque that nothing can be seen of the development of the embryo 
with a lens or microscope, hence the early stages can be studied only 
by sectioning. I have not made such studies, because I considered it 
would be of little use to do so unless the earliest stages could be studied 
hour by hour, and in no case have I been certain within a day when the 
eggs were fertilized. Moreover, I have not had the same success in 
hatching out blue cod eggs in the laboratory that I have had with the 
eggs of other species. They seem to go bad very easily. 
Although I have not got these earliest stages, I have been fortunate 
enough to get some embryos just hatched out. When the eyes are 
developed they show as dark spots in the eggs. After development 
had proceeded thus far I examined the eggs at intervals and thus managed 
to get a number hatched out shortly after they were brought into the 
laboratory. This was on March 25th. The newly-hatched embryo 
or alevin as it may now be called, is 11-12 mm. in length, with develop- 
ment well advanced. A certain amount of color is produced by a number 
of fine dark spots on the head, bands of them on each side of the dorsal 
fin and a less pronounced band below the lateral line. There is no 
break in the continuity of the median fin except at the anal opening, 
but there is little of it anterior to that opening. The pectoral fins are 
present, but they are not well developed. They do not seem to ‘be used 
at all to assist respiration. There is no sign of the ventral fins. 
There is not much sign of skeletal tissues. A broad plate of cartilage 
extends for some distance under the cerebrum, but it soon narrows and 
disappears before the optic chiasma is reached. At the anterior end of 
the notochord it again appears, forming an irregular plate of consider- 
able size. A portion of it extends out to form part of the capsule of 
the ear and posteriorly it grows up around each side of the medulla 
almost to the mid-dorsal line, but this lasts only for a very short distance. 
Laterally it connects up with the articular portion of the mandible, 
which is slightly developed. There is a cartilaginous rod in each gill 
arch. The skeleton of the pectoral girdle is but slightly developed, and 
this only in the part some distance from the middle line, in the fin 
