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half carlilaginous , terminating in a filament. The five upper 
pairs of rays are of equal length; the sixth, the lowest pair, 
is a little shorter and the rays are fixed across each other. 
The four upper pairs have their bases in contact (imbri- 
catim). The two lower pairs are separated from the for- 
mer and from one another, by an interval. The lateral 
line is a groove, which commences high on the side, at the 
posterior third of the head. From thence it gently descends 
a short distance (about the length of the head ), behind the 
gillopening, when it continues in the middle of the side. 
On the tail it deviates a little below the middle, and termi- 
nates within a short distance from the caudal. The line con- 
sists of small arched grooves, separated by short intervals. 
On the head appear several small lines: one pair commences 
from the eye, and proceeds in a somewhat converging direc- 
tion, over the vertex to the occiput; a second commences beneat 
the eye and extends to the middle of the cheek. Five pores 
are pierced through the vertical surface of the head: one 
pair behind the anterior nasal apertures, a second between 
the eyes and the muzzle, and the fiflh pore on the vertex , 
a little behind the posterior nasal apertures. The skin is 
smooth , without scales, lubricated by a copious muecous se- 
cretion. Specimens which have been preserved in spirits of 
wine, acquire numerous fine circular folds, somewhat resem- 
bling those of Zchthyophis glutinosus. The form of the body 
is nearly cylindrical, slightly tapering towards the tail; at (he 
anus the abdominal outline becomes suddenly contracted. The 
greatest vertical diameter of the body is in older individuals 
contained from 21 to 24 times in the total length, but, in 
younger individuals, from 27 to 30 times. The tail with its 
three united fins, is much compressed, lanceolate, gradually 
widening towards the termination of the anterior third; from 
thence the vertical diameter gradually decreases. The length 
of the tail is contained from 3, to 4 times in the total 
length. The greatest vertical diameter varies from 1/4, to V53 
of the total length. — The dorsal and anal fin are thick at 
