No. 2.] GRAMMICOLEPIS BRACHIUSCULUS. 283 
The opisthotic (Op.O.) is large and occupies its usual position, 
as generally found, in the cranium of the teleosts. Its posterior 
margin is pierced by a conspicuous foramen for the exit of the 
glossopharyngeal nerve from the brain-case. The intersutural 
traces defining its borders are easily made out in the specimen, 
and this element contributes not a little to the lateral wall of 
the cranial cavity, —a large vacuity existing after its disarticu- 
lation. 
Each eroccipital (E.O.) develops at the outer sides of the ver- 
tically oval foramen magnum, a fan-shaped, bony thickening 
(Fig. 5), which nearly meets at the middle point above. 
Figure 5.— Posterior aspect of the cranium of Grammicolepis brachiusculus ; life 
size. Letters have the same significance as in former figures. The cranium is repre- 
sented as resting upon its anterior face on the horizontal plane, the line of sight 
being perpendicular to the latter, and passing through the imaginary centre of the 
foramen magnum. 
Further, these bones spread out so as to complete the hinder 
cranial wall, where the supraoccipital and osseous elements at 
the lateral angles have failed to do so. 
Now a number of the bones required to complete the skull of 
this fish have been lost, and, as I said before, the others in my 
possession are too much out of shape, from their fragile nature, 
for me to decide, with any degree of certainty, as to their several 
proper positions. This is much to be regretted, as I expect a 
complete skull of Grammicolepis would prove a very interesting 
and instructive object. 
