564 ALLIS. [VoL. XII. 
often separated from that bone by a considerable interval. The 
remaining rays are firmly bound by their bases to the under sur- 
face of the blade of the ceratohyal, a little beyond its median 
edge, so that this edge is left free throughout its entire length. 
From this free edge the hyohyoideus in part arises. 
Anterior to the branchiostegal rays, the hyohyoideus runs 
forward and inward, a broad, continuous band, thick at the lateral 
edge, but very thin at the median one, where, in its anterior por- 
tion, it passes beyond the middle line of the body, and overlaps 
the muscle of the opposite side to such an extent that at their 
insertions the two muscles are often nearly but not entirely 
superimposed. The muscle of the left side lies superficial to that 
of the right side, and the two end in front in a common, curved, 
tendinous line, attached at each end by strong tendons to the 
ventral surface of the hypohyals. Each of the two muscles has 
its own tendon at either end of the common anterior margin, 
but the tendons at each end unite more or less completely as 
they approach their insertion, so that a single tendon is formed, 
which lies in the extended line of the curved front edge of the 
muscles. This single tendon then separates into two smaller ten- 
dons, one of which continues in the direction of the main tendon, 
and is inserted on the under anterior surface of the hypohyal. 
The other turns sharply forward and medianward, and splits up 
into numerous, smaller, slender tendons, which spread out finger- 
like over the under surface of the hypohyal, and are inserted on 
it, and in the tough tissue in front of it toward the tip of the 
tongue, the tendons of the one side overlapping and crossing 
beyond those of the other. No muscle fibres extend onto or 
into the tongue ; but the presence of such a network of inter- 
crossing tendons, onto which muscle fibres or their tendons are 
inserted, seems to indicate an earlier stage in, or perhaps a dif- 
ferent manner for, the “muscularization”’ of the tongue than 
that given by Gegenbaur (No. 45). The tongue in Amia can 
certainly not be considered as wanting a direct and definite con- 
nection with muscle fibres which are not in any way associated 
with a glandular system. 
The two hyohyoidei are not continuous anteriorly; they 
merely end in curved, tendinous edges, which are superimposed 
