6 
specimen there are four dorsal spines, the most anterior in position being 3 mm. 
long and the fourth 0.5 mm., the other two, intermediate in position, being also 
intermediate in size. The ventral fins possess two rays, the outer or the longer 
ray being 4 mm. long and the inner about 3 mm. The bud of a third ray is 
just beginning to appear. The rays bear dense patches of black pigment, 
especially towards their extremities. The pectoral fins are pad-like structures 
in which the rays are beginning to be differentiated. The other specimens, 
8.5 mm. and 9 mm. in length, do not differ materially from the first, showing 
merely a corresponding increase in the size of the parts. The second ray of the 
ventral fin in the 9 mm. specimen has lengthened considerably and the third ray 
is now 0.5 mm. long. In all three specimens a continuous median fin surrounds 
the trunk and caudal region. Two large patches of black dendriform pigment 
are present on each side of the trunk and a third is present near the caudal 
extremity. The dorsal portion and the region of the body covered by the 
pectoral fins are also heavily pigmented. The lower jaw protrudes beyond the 
upper and bears a single row of conical teeth. A few small teeth were also 
visible on the upper jaw. 
On the same date that these specimens in the larval stage were taken Capt. 
Arthur Calder, of the Biological boat Prince, captured with a dip-net a young 
Lophius, which was swimming on the surface at Brazil Rock. This specimen 
is in the post-larval stagé and approximates very closely the 30 mm. post-larval 
stage described and figured by Agassiz. As some doubt apparently exists con- 
cerning this stage, so grotesque in appearance, a few details will be given in con- 
firmation of Agassiz’s observations. The specimen, however,”is apparently 
abnormal in that the frontal surface of the head forms almost a right angle with 
the axis of the trunk. It is true that this angle decreases with growth, but there 
is only 4 mm. difference in length between this specimen and Agassiz’s, which is 
hardly sufficient to account for so great a change. Moreover, the younger 
larval stage 9 mm. in length does not show so great a cephalic angle, which in- 
dicates that the Brazil Rock specimen is, in this respect, abnormal. 
The Brazil Rock specimen has a total length of 26 mm. measured from tip 
of lower jaw to extremity of tail. The greatest breadth of head is 7 mm.; greatest 
height, 9 mm.; distance between eyes, 3.5 mm.; diameter of eye, 1.5 mm. 
The median fins are all differentiated, though connected with one another by 
a median fold at the base, and have well-developed fin rays. The anterior 
dorsal spines, representing together the anterior dorsal fin, are six in number. 
The first three are isolated from one another. The most anterior of these situated 
2mm. behind tip of jaw, though longest in adult stage, is in this stage the shortest, 
as figured by Agassiz. The first dorsal spine is 4 mm. long with a curved and 
flattened tip; the second 7.5 mm. and the third 8 mm. long. Then follow 
three dorsal spines connected by a membrane and forming the dorsal finlet, 
the first and longest ray being 6.5 mm. in length. Posterior to these six spines, 
forming together the anterior dorsal fin, is the second or posterior dorsal, having 
a-length measured at the base of 8 mm. and a breadth expanded of 10 mm. 
The caudal fin is 7 mm. long. The pectoral fins are fan-shaped structures held 
erect and having a greatest breadth expanded of 14 mm. and a depth of 9 mm, 
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