490 ALLIS. [VoL. II. 
and the three groups of the supratemporal line all lie superfi- 
cial to the extrascapula. They extend slightly beyond its mar- 
gins, and form, with the same groups on the other side of the 
head, a nearly continuous series which lies behind the line of 
the pre-opercular fold and in front of the first row of scales. 
In the 17-inch specimen there were ninety-four pores in these 
five groups on one side of the head; in the 20}-inch one, one 
hundred and two; and in the 27-inch one, two hundred and 
fourteen. In the skull there were one hundred and ten open- 
ings. 
Group 20 lies ona fleshy pad above, and immediately in front 
of, the upper end of the opercular opening, behind the extra- 
scapula and opposite the first two or three scales behind that 
bone. 
Group 21 is much smaller than No. 20, and lies on a similar 
but smaller pad above and behind the upper end of the opercular 
opening, above the upper edge of the supraclavicula and oppo- 
site the third and fourth, fourth and fifth, or fourth, fifth, and 
sixth scales, behind the extrascapula. The pores of this group 
often extend onto the bases of the scales, but when this occurs, 
the canals leading to them lie entirely in the dermis or epider- 
mis, not entering the bony part of the scale at all. There were 
in groups 20 and 21, in the 17-inch specimen, thirty-nine pores ; 
in the 20}-inch one, fifty ; in the 27-inch one, ninety-one; and 
in the skull forty-one openings. 
Groups 20 and 21 and those found on the first five scales of 
the lateral line in the 27-inch specimen-are shown in Fig. 39, PI. 
XXXIX. The hind edge of the gill cover is cut off in order to 
show the position of the supraclavicula and the arrangement of 
the scales immediately behind it. In this specimen, the pores 
of group 21 extended onto the base of the sixth scale, counting 
always from the hind edge of the extrascapula, and the lateral 
line began on the eighth. In the 17 and 203 inch ones, group 
21 only extended to the level of the fifth scale; and the lateral 
line began on the seventh. 
2. Lateral Line of the Body.—The first scale of the lateral 
line is always irregular, and without the thin portion which 
extends beyond the bone in the other scales, and which gives 
them their rounded outline. Between it and the hind edge of 
the supraclavicula there is a single large opening (Fig. 39, PI. 
