GILL | LIFE HISTORIES OF TOADFISHES 41I 
H. Gilbert. The naked lateral areas on the upper surface of the head 
in the midst of the exposed granuliferous bones have been asserted 
to be the seats of a certain electric manifestation. According to 
Henshall, it was exhibited by the Florida fish (4. y-grecum), and 
Gilbert (1896), in a note on the Mexican Pacific coast species 
(A. sephyreus), remarked that “a distinct electric shock was given 
by this fish when alive, the electric organs being in the fleshy areas 
on top of head behind eyes.” Such a manifestation certainly de- 
serves more attention that it has received.* 
Nothing is known of the embryology and development of any 
Astroscope. One notable fact in their growth, however, is that 
the naked areas on the crown and the scales become manifest rather 
late, for specimens over two inches long are naked (i. ¢., scaleless) 
and the naked coronal areas do not stand out in strong relief. On 
a young specimen the Uranoscopus anoplus was based, as well as 
the genus Astroscopus. 
Two well-defined species of the genus Astroscopus occur along 
the eastern coast of the United States and may be distinguished as 
follows: 
Astroscopus y-grecum. 
Naked postocular areas much longer than wide; preorbital spines 
reduced to two knobs in the adults; color yellowish brown with 
oblong spots between larger interspaces; small dots on postocular 
areas; long spots on back and sides of head, and dots on cheeks; 
spots, larger and less crowded than those of A. guttatus, on back 
and sides and extending to near the caudal fin; hindmost edge of 
dorsal fin white. 
Astroscopus guttatus. 
Naked postocular spaces not longer than wide; two distinctly 
defined spines on front of preorbital; color dark and reddish brown, 
with numerous small spots on naked postorbital areas and on sides, 
becoming larger backwards; a lateral dark band on the posterior 
half of the trunk and on the tail; a cross band on the sides and 
lower edge of the caudal peduncle; ventrals with interspaces be- 
tween inner rays, third to fifth, dark, while in y-gr@cum the ventral 
fins are uniformly whitish. 
There is a remarkable difference between the young and old; 
some up to a length of nearly or quite three inches are scaleless. 
* Since the above paragraphs were written Dr. Ulric Dahlgren, of Princeton, 
has visited the coast for the purpose of observing the Astroscope and has 
verified the electric power of the fish. A preliminary note has been published 
in Science (March 23, 1906, p. 4690, 470) and details may be expected later. 
