OBSERVATIONS ON FISH SCALES. 
161 
In Box vulgaris (Vienna Museum; M. C. Z.) the scales are about 334 mm. long and 5^ broad, with 
the nucleus central and about 10 widely spreading basal radial folds. This is much like Stenotomus, 
differing in the less apical nucleus; the sloping sides, making the lower margin the broadest part; the 
broad apical region with the small quadrate elements distinct over the greater part, with no marked 
difference between the marginal and submarginal ones; and the much more oblique lateral circuli. 
(PI. xxxviii, fig. 34.) 
Dr. G. A. Boulenger kindly collected for me scales of Dentex vulgaris Cuvier, from a fish 2 feet 10 
inches long, in the Grimsby Market. The scales vary very much in size and form; a large one is about 
21 mm. long and 27 broad; an unusually broad one is about 13 mm. long and 21 broad; another is 15^ 
long and 18 broad. These all come from the side of the fish. The circuli are excessively fine, and the 
lateral ones are little oblique, w r hereas in Box they are extremely oblique, reaching the margin at a large 
angle. The basal radial system is variably and often poorly developed, and the radii are not very numer¬ 
ous. The apical margin appears cycloid, but the apical field has a fine half obliterated honey-comb-like 
Fig. 25. —Orthopristis chalceus 
(Haemulidae). Ctenoid struc¬ 
tures. The spots between the 
teeth are ferruginous pigment 
spots. Bureau of Fisheries. 
Fig. 26. —Stenotomus chry- 
sops (Sparidae). Ctenoid 
structures. Bureau of 
Fisheries. 
structure representing the ctenoid patch. Curiously, the skin over the apical field is marked with a very 
distinct network of polygonal cells, corresponding to the structure beneath. The nucleus is apical of 
the middle. 
In Dr. A. S. Woodward’s Catalogue of Fossil Fishes (1901), and in earlier works, Dentex appears 
among the Percidse (sens. lat.). Dr. Woodward states that Dentex, Genes, etc., are intermediate between 
the Percidae and Sparidae. 
M£NIDj£. Picarels. (PI. xxxviii, fig. 35.) 
I have the scales of an undetermined species of Smaris (Spicara ) from Trieste (M. C. Z., 10436). 
They are about 2^ mm. long and 3% broad; nucleus a little above the middle; about 10 strong widely 
spreading basal radii; sides sloping, so that the base is much the widest part; lateral circuli extremely 
oblique, but wanting in upper lateral region; apical margin strongly angled in the middle; apical margi¬ 
nal teeth sharp, and below them about two rows of broad subquadrate elements, below which the apical 
field is almost without sculpture. . 
This may be regarded as an extreme development of the type of Box. The oblique lateral circuli 
also suggest Apogonichthys, which is, however, very different in the apical region. 
GERRIDj®. Mojarras. 
The “broad shad,” Xystcema cinereum (Walbaum), from La Paz Harbor (Albatross) has trans- 
versely oval or oblong scales about 6 mm. long and 7 broad, the laterobasal comers rounded, and the 
basal radii few (about 5) and more or less irregularly placed. The lower margin is only feebly cremate. 
The thin apical field shows rudiments of the usual ctenoid structures of Acanthopterygians, reduced to 
89970°—13-4 
