PACIFIC SCIENCE, Vol. XIV, October I960 
376 
brotulids (Gosline, 1953, table 3). The opistho- 
tic of Otophidium (Fig. 1 c) and Snyderidia 
(Fig. lb) is expanded. 
Three other cranial features of Otophidium 
and Snyderidia seem worth noting. In Otophi- 
dium the exoccipital facet for the articulation 
of the first vertebra forms a single concave wall 
of nearly uniform depth; in the available bro- 
tulids and in Snyderidia this articulation is 
formed by the usual two projecting pads. In 
Snyderidia I can find no trace of a suture be- 
tween the frontals (Fig. la). Finally, in the 
same genus, as frequently in carapids, there is 
a greatly enlarged canine tooth at the front of 
the vomer (Fig. lb). 
Suspensorium: Regan (1912) has used the 
fusion vs. nonfusion of the ectopterygoid and 
mesopterygoid as a distinction between the 
Ophidiidae and the Brotulidae. In the three 
brotulid skeletons available the mesopterygoid 
and ectopterygoid are indeed joined by suture, 
whereas in the ophidiid they are fused. Emery 
(1880, pi. 3) shows the mesopterygoid and 
ectopterygoid of two species of carapids as 
suturally joined. In Snyderidia (Fig. 2)1 have 
been able to find no trace of a suture between 
the ecto- and the mesopterygoid, but, as already 
noted, I have had difficulty locating the sutures 
between several of the other head bones in this 
specimen. 
Another variable character in the ophidioid 
fishes is the position and size of the metaptery- 
goid. In Brotula this bone completely separates 
the hyomandibula and mesopterygoid. In the 
other two brotulid skeletons, as in Otophidium, 
the latter two bones barely meet in front of the 
metapterygoid, and in Snyderidia ( Fig. 2 ) there 
is a broad mesopterygoid-hyomandibula junc- 
tion in front of the metapterygoid. 
In Snyderidia (Fig. 2), as in Otophidium, 
the hyomandibular strut that runs back across 
the inner face of the preopercle to form the 
articulation with the opercle is long and narrow, 
not short and strong as in Brotula. 
Opercular bones: The opercle in Snyderidia 
is formed of two struts extending out like the 
wings of a V from the opercle-hyomandibular 
articulation. The upper of these wings ends in 
a point; the lower is broadly rounded distally. 
The structure is not very different from that in 
Fig. 1. Skulls of: Snyderidia, a, top view, b, side 
view; c, of Otophidium, side view. The dotted line in 
c represents the approximate limit of the occipital 
crest, bo, Basioccipital; eo, exoccipital; ep, epiotic; fr, 
frontals; me, mesethmoid; op, opisthotic; pa, parietal; 
pf, prefrontal; po, prootic; ps, parasphenoid; pt, pterc- 
tic; so, supraoccipital; sp, sphenotic; vo, vomer. 
Otophidium' or the illustrations of carapids 
given by Emery ( 1880, pi. 3). 
Jaws: Except for the large canine tooth at the 
front of the premaxillary of Snyderidia, I am 
unable to find significant differences between it, 
Otophidium, and the three brotulid genera. The 
upper jaw of Snyderidia is about as drawn by 
Emery (1880, pi. 3, fig. 25) for f Tierasfer 
dentatus.” 
The lower jaw in carapids has been dealt with 
recently by Arnold (1956) who distinguishes 
three types within the family. The mandible of 
Snyderidia (Fig. 2) very definitely falls with 
type B of Arnold ( 1956, fig. 3; see also Emery, 
1880, pi. 3, fig. 25). The lower double rim of 
this jaw type is also found in Otophidium but 
not in the available brotulid skeletons. 
A curious feature of the lower jaw of Sny- 
deridia is that in dissection the angular on both 
sides, together with its ligamentous attachment 
