34 
PACIFIC SCIENCE, Vol. XIV, January I960 
FIG. 6. Right half of hyoid apparatus of Pseudogramma, external view with the urohyal dislocated, br, 
Branchiostegal ray; ce, ceratohyal; eh, epihyal; gl, glossohyal; hy, hypohyal; ih, interhyal; ur, urohyal. 
vertebra) number 26, in Plesiops 25, and in 
Pseudo chromis 26. The first interneural in Pseu- 
dogramma, Plesiops, and Pseudo chromis extends 
between the second and third neural arches; 
Epinephelus was not examined for this character. 
In Epinephelus and Pseudogramma the second 
interhaemal is very strong and runs up to wedge 
into the posterior face of a haemal arch. In 
Plesiops and, especially, Pseudo chromis, the 
second interhaemal is considerably weaker. 
Caudal Skeleton. The caudal skeleton of all 
four genera appears to be built on the same plan 
(Fig. 8), though there is considerable minor 
variation, especially in the amount of fusion. 
Thus there may be two or three epurals and 
three to five hypurals. 
Summary of Internal Differences. Though 
the internal, especially the osteological, differ- 
ences between Epinephelus, Pseudogramma, Ple- 
siops, and Pseudo chromis are slight, they are not 
entirely negligible. Thus each of the three ser- 
ranid offshoots stands apart in one fashion or 
another. 
Pseudogramma differs from the other genera 
in the enlarged nasal organ, the preopercular 
spine with its associated glandular area, and in 
having two pyloric caecae. 
Plesiops appears hardest to define on the basis 
of internal features. Perhaps the hook on the 
anterior face of the cleithrum and the double 
border to the preopercle are the most salient. 
Pseudochromis differs immediately from the 
others in the mouth parts. The teeth are rigid; 
the maxillary bends around the premaxillary and 
lacks a supramaxillary; the premaxillary pedicels 
are elongate; and the palatines are movably 
articulated with the remainder of the suspen- 
sorium. 
External Features. With one exception the 
external features of the fishes investigated will 
not be treated on a genus-to-genus basis as they 
have been noted by every ichthyologist who has 
worked with these groups. However, some of 
them will be taken up in the discussion of rela- 
tionships in the next section. 
The exception concerns the number of 
branched caudal rays. The perciform fishes are 
often stated to have 1 5 or fewer branched caudal 
rays. In Epinephelus the usual 15 were counted 
in 3 specimens. However, 16 are present in the 
one specimen available of Grammistes. The 
stained specimen of Pseudogramma has 17, as 
does that of Pseudochromis. In the 5 available 
specimens of Plesiops, one has 15, one 16, and 
three 17. 
