Dr. T. Gill on Esox Lewini. 159 



cruise in the Mediterranean, and kindly presented by him to 

 the British Museum, there is a remarkable new species of 

 Zootoca, which he found inhabiting in great numbers a very 

 small island (Ayre Island) on the south-east of Minorca. I 

 have named it, after its discoverer, Zootoca Lilfordi) its 

 distinguishing characters are as follows : — 



All the upper parts deep shining black, lower parts of a 

 beautiful sapphire-blue. Back and sides covered with minute, 

 round, granular scales, of which there are between 90 and 100 

 in one of the transverse series in the middle of the length of 

 the trunk. Ventral shields in six longitudinal and twenty- 

 seven or twenty-eight transverse series. Collar very distinct. 

 Gular scales much larger than those of the body, and 

 slightly larger than those on the temples. Temporal scales, 

 uniformly granular, with the exception of a large central 

 scute. Scutellation of the head otherwise similar to that of 

 Z. muralis. 



The largest of four examples is 5| inches long, of which 

 the tail takes 3£ inches. 



To this species I refer also the lizard which is so common 

 on the Filfola Rock, a very small island south of Malta. 

 Structurally there is no difference between them ; but the 

 Filfola race, instead of being uniform black above, has the 

 back and sides ornamented with small bluish-green specks, 

 and the lower parts are bluish black. It appears also to 

 attain to a larger size, viz. 8^ inches, of which the tail takes 

 5| inches. 



The occurrence on these small islands of a black repre- 

 sentative of the continental Zootoca muralis is a remarkable 

 fact, which deserves attention inasmuch as it is in accordance 

 with other instances of a race having assumed a deep black 

 coloration when confined to a small island — for example, Co- 

 ronella phocarum from Robben Island. 



XXIII. — On the Identity of Esox Lewini with, the Dinolestes 

 Miilleri of Klunzinger. By Theodore Gill. 



In the tenth volume (" the class Pisces ") of the ' Animal 

 Kingdom' of Cuvier, edited by Edward Griffith (1834), are 



