180 
ACTINOPTEEYGII. 
recurved teeth in both jaws. The relatively great extent 
of the articulo-angular element of the mandible is 
distinct, while a few of the slender branchiostegal rays 
occur below. The clavicle is shown to be robust, and the 
pelvic fin-support expanded. Remains of an undigested 
individual, apparently of Leptotraclielus gracilis, extend 
along the whole length of the abdominal region ; and 
there are some rounded bodies clustered in advance of 
the pelvic fins, which may be ova. Lewis Coll. 
46524. Small imperfect fish, wanting the rostral end of the skull ; 
Sahel Alma. Lewis Coll. 
47361-62. Two imperfect examples of the trunk ; Sahel Alma. 
Lewis Coll. 
The following specimen probably belongs to a large individual 
of Leptotraclielus triqueter, but its specific determination is un¬ 
certain : — 
P, 1903, P. 4250. Vertically crushed skull and pectoral arch, in 
counterpart; Sahel Alma. The rostral region and an 
impression of the remainder of the cranial roof exhibit an 
ornamentation of delicate raised lines and rows of small 
tubercles; those on the mesethmoid in a longitudinal 
direction, those on the hinder part of the frontal more or 
less radiating and scarcely reaching its posterior border. 
The mandibular ramus of the left side is shown to be 
similarly ornamented with longitudinal series of fine 
tubercles. The slender teeth are clustered as usual. 
Remains of the slender spaced branchiostegal rays are 
seen, about 12 on the left side. The right pectoral fin 
exhibits 11 rays, all distantly articulated at the distal 
end, and all except the first two bifurcating twice distally. 
The anterior vertebral centra are not more than twice as 
long as deep. Egerton Ennishillen Colls. 
Leptotrachelus gracilis, Davis. 
1837. Leptotrachelus gracilis, J. W. Davis, Trans. Roy. Dublin Soc. [2] 
vol. iii. p. 623, pi. xxxviii. fig. 3. 
Type. Nearly complete fish ; British Museum. 
A very slender species attaining a length of about 0*5, but usually 
smaller. Length of head with opercular apparatus contained about 
five and a half times in the total length to the base of the caudal 
