96 
PACIFIC SCIENCE, Vol. XVII, January 1963 
most ray in Parapercis and Crystallodytes. Judg- 
ing from the material available, it appears that 
the uppermost pectoral ray is homologous 
whether splintlike or segmented, for it has the 
same very peculiar basal structure. Like other 
soft rays it consists of two halves. However, 
in the uppermost pectoral ray the two halves 
are usually not mirror images of one another. 
Rather, the scapula articulates with a facet that 
lies entirely on the inner "half” of the ray 
(except, among the fishes investigated, in Hy- 
poptychus and Trip ter ygion ) , An inquiry into 
this peculiarity has shown that the scopeliform 
genus Sy nodus has a small bony nodule that 
lies between two equal halves, but is attached 
to the inner. As Starks (1930: 238) noted, 
Fig. 7. Right pectoral girdles, external view, of a, 
Tripterygion atriceps; b, Bleekeria gilli; c, Hypo- 
ptychus dybowskii; and d, Ammodytes tobianus. Only 
the uppermost and lowermost pectoral rays are shown 
in a, b and d; the top of the pectoral girdle is not 
drawn in b; and the lower postcleithmm is not in- 
dicated in a. ac, Actinost; cl, cleithrum; co, coracoid; 
pc, postcleithrum; pe, pelvic girdle; pm, postcleithrum; 
py, pectoral ray; sc, scapula; and scl, supracleithmm. 
this nodule probably represents a modified ac- 
tinost, which in many higher teleosts became 
incorporated into the inner, articular "half” of 
the uppermost pectoral ray (Fig. lb, d). 
The pectoral girdles of Tripterygion and of 
the ammodytoids are shown in Fig. 7. Those 
of the ammodytoids are peculiar in having the j 
supracleithra and cleithra more or less vertically 
aligned. 
There are two postcleithra in Parapercis, 
Tripterygion, Ammodytes, and Bleekeria, and 
apparently not any in Crystallodytes and Hy- 
poptychus, 
PELVIC FIN: Pelvic fins are lacking in the 
three ammodytoids studied here. However, two 
splintlike pelvic girdle elements are to be found J! 
in Bleekeria (Fig. 7b), and a small pelvic fin 
of a spine and three rays, located somewhat 
ahead of the pelvic bases, occurs in the related 
ammodytid genus Embolichthys (Jordan, 1902). 
The three other fishes studied here also have 
the pelvics originating ahead of the pectoral 
bases. Parapercis has a pelvic spine and five 
branched rays, the fourth considerably the long- 
est. Crystallodytes has a short pelvic consisting 
of a spine and five unbranched but segmented 
rays. In Tripterygion there are two well- 
developed unbranched, but segmented, rays; 
there is no spine. In all three fishes the pelvic 
girdle articulates anteriorly with the cleithra.' 
In Crystallodytes (Fig. 8 d), the two halves of 
the pelvic girdle are rather widely separated an- 
teriorly; in Parapercis (Fig. 8b) they are united 
for nearly their entire length; in Tripterygion 
(Fig. 8c) the two halves are not only united, 
but anteriorly they seem to have completely 
fused. Futhermore, Tripterygion has the pelvic 
girdle firmly wedged between the cleithra. 
VETEBRAL COLUMN AND RIBS: Parapercis 
has 30 ( 10 -j- 20) vertebrae (including the uro- 
style); Tripterygion , 34 (10 + 24); Crystal- 
lodytes, 55 (29 + 26); Ammodytes lanceo- 
latns, according to Regan (1913: 137), 69 
(40 + 29); Bleekeria gilli, according to 
Duncker and Mohr (1939: 13), 57 (32 + 25); 
and Hypoptycbus , 55 (31 + 24). 
In Parapercis, Tripterygion, Ammodytes , and 
Bleekeria there are two sets of ribs. The lower, 
or pleural, ribs start from the 3rd vertebra; the 
upper, or epipieural, ribs start from the 1st, 
