154 
the isthmus, and its base, which can be received into a groove, is 
two-thirds that of the second ; a low fold of skin runs from the first fin 
to within two eye-diameters of the second; the length of the spine 
is one-eighth longer than the head ; it is acute and serrated in front, 
but flat or slightly concave behind, each posterior edge having in its 
upper half a series of retrose serrations ; the rays are set on a high 
base, and the posterior ones are fairly distinct : the second fin is one- 
fourth lower than the first, and, following the high anterior lobe, falls 
gradually, terminating in advance of the anal: the length of the pec- 
toral, exclusive of its base, is one - fourth that of the head, and it 
extends almost to the second dorsal; the ventral is inserted wholly in 
advance of that fin, and its length is 1-5 in the head; the anal lies 
directly in advance of the caudal lobe, and is long and narrow, its 
width one-third its length, which is 1-8 in the head; the caudal is 
deeply rayed below anteriorly, and the rays are continued to the end 
of the filament ; there is a slight ray on the upper portion also; the 
upper insertion of the caudal is above the middle of the anal fin; the 
lateral line, postertor to the head, runs a direct though wavy course to 
above the caudal lobe, where it dips suddenly to the lower margin, 
thence to the end of the fin. 
Teeth—It would appear that the teeth undergo some change 
during the life of the animal, but I am not at present in a position to 
discuss the matter at length. The following references are to Gar- 
man’s figures*of the teeth of Chimeroids.* Young specimens exhibit 
teeth like C. smythw (vi, 1, 2), the vomerines forming a transverse 
cutting-edge; the palatines bear two pairs of ridges, of which the 
inner pair is the longer ; there are two ridges on the mandibular plate, 
which operate between those of the palatines. In older specimens 
the palatine ridges are less pronounced, and the mandibular ridges 
disappear, the plate being flattened and incised anteriorly; these 
resemble C. callorynchus (vii, 7, 8), though the vomerine teeth still 
present the acute aspect ; the jaws of an evidently very large specimen 
in the collection appear more like C. tritoris (vi, 9), the vomerine teeth 
have not a transverse aspect, while there is no trace of palatine or 
mandibular ridges, and the latter are rounded and have the front 
margin entire, as in the figure. 
Colour.—Greenish yellow with black markings disposed in three 
longitudinal series along each side, one along the back, another follow- 
ing the course of the lateral line, and a third below it, terminating at 
the ventral; in some examples the lines are complete, in others they 
are broken up into blotches, and may be almost absent ; the markings 
on the fins vary greatly also. 
Bashford Dean has supplied a list of existing Chimeroids,t but 
the uncertainty there expressed shows that much yet requires to be 
* Garman, Bull. Mus. Comp. Zool., xli, 1904, p. 245, pl. vi, vii. 
+ Dean, Carnegie Inst. Wash. Pub. 32, 1906, pp. 6, 7. 
