16 
believed, be revealed to us by the microscope. He enume- 
rated some of our other food fishes, more or less resembling 
in form those already named, and a reference to which, he 
said, would elucidate his next point. The brill, plaice, dab, 
and flounder, belonged to the same family as the turbot; the 
rays are represented by the skate and thornback ; the gadide 
by the cod, haddock, and whiting; the scornberide by the 
mackerel ; the clupeidw by the herring, pilchard, sprat, shad, 
and whitebait ; and other genera by the mullets, bass, dory, 
gurnard, &. ‘*The second noticeable feature which I men- 
tioned ” (continued Mr. Lee)—‘‘ their variety of colour—is 
perceptible at a glance, but the difference in their skin-covering 
demands more careful attention, and more lengthened com- 
ment. The turbot, for instance, has no proper scales, but is 
furnished with isolated plates, or tubercles, beneath its skin, 
which connect it with the placoid order of fishes—the rays 
and sharks. These have horny plates instead of scales, which 
are often armed with median spines, as in the thornback, or 
are bristled with small sharp eminences, like a rough file, as 
in the ‘‘shagreen”’ of the sharks and dog-fishes. And yet 
the congeners of the turbot—the brill, sole, &c.—are com- 
pletely covered, both on their upper and under surfaces, with 
over-lapping ctenoid (comb-like) scales, like those of the 
perch. The salmon, the herring, the cod, the eel, and the 
families which they represent, have all cycloid scales, smooth 
and simple on the margin, and presenting the appearance of 
concentric rings. The two first-named are shielded by these 
circular, or ovoid, over-lapping scales. In the salmon they are 
firmly fixed ; in the herring they are so loosely inserted that 
they are easily detached by the slightest touch. In the eel 
and cod, however, they are not on the outer surface, but 
beneath the epidermis, and from the skin of the former, 
especially, a novice might find some difficulty in extracting 
them. The eel was long supposed to be a scaleless fish, and 
and as such is still avoided by the Jews as a forbidden article 
of food; but you have only to wash the skin of one to see, 
through the transparent membrane, the scales arranged in 
curious pattern beneath. This is still more effectively dis- 
played if a portion of the skin of an eel or cod be dried, 
mounted in Canada balsam, and submitted to the polariscope. 
A microscopical examination of the structure of fish scales 
and their pigmert-cells may some day lead us to understand 
a phenomenon for which at present we are able only very 
imperfectly to account, and it is an interesting and imstructive 
study, which I comménd to your attention. It is a well- 
known fact, and one which you can verify for yourselves in 
any aquarium, that fishes, especially flat-fishes, have the 
