5 
and the structure of the embryo quite clear. Figure 1 shows a stage in which 
the blastoderm covers about five sixths of the surface of the yolk. The em- 
bryonic ring is very narrow but distinctly marked. The embryo extends over 
approximately one-half the circumference of the yolk, the perpendicular distance 
from head to caudal extremity being 1.2mm. The pigment spots are now much 
larger and branch frequently, connecting with each other. They cover the 
larger portion of the blastoderm, only that portion opposite the embryo being 
free of pigment. At this stage the optic sacs are beginning to be differentiated 
and just posterior to them, the pigment spots extend across the median dorsal 
region. A large oil-globule has its position opposite the caudal end of the 
embryo. Sometimes a second oil-globule near the large one is present at this 
stage. In some eggs that portion of the blastoderm covering the oil-globule 
Fig. 1. Egg showing embryo at more advanced stage. es, embryonic shield; og, oil-globule; 
er, embryonic ring; y, yolk. 
becomes more densely pigmented than elsewhere, with the exception of the 
lateral parts of the embryo, but in others the oil-globule is yet quite free of | 
pigmentation. There is no indication at this stage of the formation of somites 
In a few eggs the blastoderm has almost surrounded the yolk, the blastopore 
having now a width about equal to the diameter of the oil-globule. There is no 
further differentiation of the embryo shown at the slightly older stage except 
that the head is more distinctly marked off. 
In the summer of 1921 three specimens in early larval stages were observed 
among material collected at Brazil Rock, off Barrington Passage, Shelburne 
County, N.S. These specimens were taken with a young fish trawl on the 
9th of August at a depth of 25 to 30 metres. They are but 8 to 9 mm. in length, 
measured from the tip of the lower jaw to the extremity of the tail. In the 8 mm. 
17 
