1 1 
and mechanical Action of the Muscles of Fishes. 
iii a half-penniform manner. The recti abdominis are also di- 
vided into short masses by transverse tendons, and all these 
muscles are conjointly employed in the action of leaping. 
Perhaps these observations may indicate the reason for 
that diversity in the lengths of various muscles, which act 
together ; thus, organs of velocity are joined with those of 
power, and mutually co-operate to produce a simultaneous 
effect 
Description of Plate I. 
The drawing was made from a cod which had been coagu- 
lated by heat, in a case of plaister of Paris, the skin being 
taken away, and an equal portion of the flakes carefully 
removed from each series, to exhibit their several directions. 
The subject was reduced to the present size by accurate 
measurements. 
aa, Muscles which extend the pectoral and jugular fins. 
bbbbb, Oblique muscles, which erect the rays of the single 
fins. 
cc, Muscles which depress the rays. 
dd, Muscles which extend the rays of the tail. 
ee, Interosseal muscles, which close the rays. 
ff, The dorsal series of muscular flakes. 
gg. The vertebral series. 
hh, The abdominal series. 
ii, The ventral series. 
kkk, Three superficial nerves which run longitudinally be- 
tween the series of flakes. 
/, Posterior surface of a dorsal flake. 
m, Posterior surface of an abdominal flake. 
C 2 
