47(3 



Tinca. 



Tinca vulgaris Cuvier = l'inea tinca. Constantinople (Milligan) 

 Scales about ü mm long and 21/2 broad, with radii all around; nuclear 

 region very near the base. This scale is absolutely unique, so far as 

 my knowledge goes. The fossil species of Tinea from Oeningen agree. 

 The American Algansea iincclla has rather similar but broader and much 

 smaller scales, with the apical circuii very coarse, Avhereas in Tinea 

 they are extremely fine. The Algaiisea scale is only about 2 mm long. 

 ScJiixothorax biddulphii Günther, has an elongate scale, shaped nearly 

 as in Tinea., but the circuii are very coarse and the radii are relatively 

 few, only about 13 altogether. In the structure of the apical circuii, 

 Algansea is like Sekixotiiorax and not like Tinca. There is a curious 

 resemblance in pattern, and indeed also in the basal nucleus, between 

 the scales of Tinea and those of the Cobitid Misgnrnus fossilis. The 

 Misgnrmis scale however, is round, or rather broader than long. 



Phoxinufi. 



Phoxinus jihoxinus. Leyn Arene'g, Merioneth (H. E. Forrest). 

 Minute scales, much broader than long, the nuclear area subcentral; 

 radii all around. Very different from the scales of Lcnciscns, and also 

 different from the so-called American Phoxinus^ which arc now refer- 

 red to Margariscus. The American genus Cl/rosonuts has scales reseml)!- 

 ing those of PJwxinns, and the fishes of both genera and brightly co- 

 lored, or at least the males in the breeding season. Whether the various 

 other European and Asiatic species assigned to PJ/oximis have similar 

 scales I do not know, but those of the North African PiioxincUns are 

 quite distinct, with no basal radii. Leueiseus helvetieus Winkler, from 

 the Miocene of Oeningen, has round scales, the circuii fine and regular, 

 strong; apical radii about seven, wide apart; basal radii separated by 

 an interval from the apical. This is apparently intermediate between 

 Leuciseus and Piioxinus., but nearer to Leueiseus. The scales of L. 

 oeningensis Agassiz, as figured, are circular, witli characteristic Piio- 

 xinus sculpture^ but on examing a fish so-labelled, I found them similar 

 to those of L. helvetieus., the basal radii very distinti. Further study of 

 these fossils is desirable. 



lihodeKS. 



Rhodcus ainarus. I do not possess the scales of this species, but 

 they are figured by F at io. They are very much broader than long, ex- 

 cept those on the caudal })eduncle, which are oval. The i)asal radii are 

 absent. 



