32 ZOOLOGY OF THE VOYAGE OF THE BEAGLE. 
eight. In the third, which commences behind the pectoral, and extends in like manner to the 
caudal, there are thirty-five. In the fourth, which commences on the breast, immediately behind 
the point of attachment of the branchial membrane to the isthmus, there are thirty, reckoning 
to behind the anal, where it unites with its fellow to form one; between this point and the 
caudal there are ten, the serratures of which are rather obsolete. The fourth pair of ridges 
are throughout their course less sharply serrated than the second and third pairs, and these last 
again rather less so than the first or dorsal pair. Between the two ventral ridges, near their 
commencement in front of the ventral fins, are six slightly serrated scales (similar to those in 
the ridges) forming on the breast a somewhat triangular patch, two single ones standing first, 
then four others in pairs. The lateral line, which is catenulated as in A. cataphractus, com- 
mences at the upper angle of the opercle, then bends downwards to take a middle course between 
the second and third ridges, which it preserves to the caudal. The first dorsal commences 
behind the seventh scale in the dorsal ridges, or at about one-third of the entire length ; it is of 
the same form as in the A. cataphractus, but contains more rays ; its membrane terminates at 
the fifteenth scale, and there are rather more than two scales between it and the second dorsal, 
which last is rather shorter and higher than the first. The rays of the first dorsal are not stouter 
than those of the second, nor relatively stouter than those of the A. cataphractus. The rays 
of the second dorsal are simple, with the second and third rather longer than the first. The 
anal answers to the second dorsal. The pectorals are rounded, and one-fifth of the entire 
length. Ventrals very narrow, and scarcely more than half the length of the pectorals. 
Position of the vent a little anterior to a line connecting the extremities of the ventrals. 
Cotour.—(In spirits.) Dusky grey above and on the sides, paler beneath ; with four broad trans- 
verse blackish fascize passing across the back and down the sides as far as the third longitudinal 
ridge of scales. The first fascia is in the region of the first half of the first dorsal ; the second 
at the commencement of the second dorsal; the third near the end of the second dorsal; the 
fourth half way between the end of the second dorsal and the caudal ; and a little beyond this 
there is a faint trace of a fifth fascia. The body is a little mottled in places with spots of the 
same dark colour as the fascie, and the fins, with the exception of the ventrals, are of the same 
hue. 
Habitat, Chiloe, (West coast of S. America). 
The absence of vomerine teeth has been considered by Cuvier as one of the 
characters serving to distinguish Aspidophorus from Cottus; but as these teeth 
are very distinctly developed in the present species, we must rather dwell upon 
the large keeled sharp-pointed scales, which envelope the body in a kind of mail, 
and, as Dr. Richardson observes,* “ give the Aspidophori a totally different aspect 
from the Coéti.” Indeed on equally strong grounds as those on which Cuvier has 
separated Pinguipes from Percis and Prionotus from Trigla, the present species, 
which possesses both vomerine and palatine teeth,{ might be made a distinct 
* Faun. Bor. Amer. Part Third, p. 49. 
+ Is it not possible that this may be found to be also the case with several of the foreign species described by 
Cuvier, in which the absence of these teeth has been rather presumed than ascertained from actual examination ? 
