396 



NOTES AND MEMORANDA. 



Polyprion cernium, Val. — Two specimens of this fish_, the stone 

 basse or wreck-fish, were obtained on September 21st. The one 

 was sent by Mr. Dunn, of Mevagissey, the other captured by hook 

 and line off Plymouth. The first specimen measured 19^ inches, 

 the second 20| inches. 



It is singular that two of these fishes, which are by no means 

 common, should have occurred at the same time. If the statement 

 to the effect that these fishes are in the habit of following wreckage 

 be true, it may be that several have arrived off our coast in this 

 manner. The fish is common at Madeira. — W. L. C. 



Scomber scomber, Linn (the Mackerel). — In sorting some young 

 fish, chiefly the '' mackerel midges ^' of Motella tricirrata which were 

 taken at the surface at the end of July by Mr. F. Klotz, of the s.s. 

 " Dominican," I found three specimens which prove to belong to this 

 species, of which the later larval stages had not hitherto been 

 recognised. 



The total lengths are respectively 13'75, 16*5, and 18'5 mm. In 

 the largest specimen the head and abdomen are about equal in 

 length, and together a little longer than the caudal region, exclu- 

 sive of the caudal fin. The eye and the snout are each about one 

 third, and the greatest height of the body is about three quarters 

 of the length of the head. The general shape of the fish is very 

 much the same as that of the young Temnodon figured by Agassiz 

 {Young Stages of Osseous Fishes, Proc. Am. Ac. Art. Sci., vol. xiv, 

 1878, pi. ii, fig. 5), but the upper jaw is slightly the longer. The 

 caudal, which is completely metamorphosed, is separate, and appears 

 to be notched in a similar manner, but is rather damaged in all my 

 specimens. The same interval occurs between the anus and the 

 anterior anal rays as in Temnodon. The differences in the rays of 

 the permanent dorsal and anal fins, which are visible in the persist- 

 ing embryonic fin-membrane of those regions, are also those of the 

 adults. In my examples the first dorsal occupies the adult position, 

 separated by a wide interval of embryonic membrane from the second. 

 The ridges from which spring the rays of the continuous anterior 

 parts of the permanent second dorsal and anal fins are continued 



