50 ON FISHES NEW TO THE BRITISH FAUNA. [Feb. 5, 



5. Notice of two Fishes new to the British Fauua. 

 By Dr. A. Gunther, F.R.S. 



[Eeceived February 5, 1889.] 

 (Plate IV.) 



1. On a Hybrid between the Roach (Leiiciscus rutilus) and the 

 Bleak (Alburuus alburnus). 



In December of last year I received from Lord Lilford a Cyprinoid 

 5| inches long which had been caught in the river Nene in 

 Northamptonshire, close to Lilford, and which he rightly supposed 

 to be a hybrid between the Roach and the Bleak. So far as I 

 know, hybridism between these two' genera has not been observed 

 hitherto, and occurrences of this form must be also scarce in the 

 river mentioned, although other hybrids, as between the Bream 

 and White Bream, between the Bream and Roach, between the 

 Bream and Rudd, are by no means scarce, and, as Lord Lilford 

 informs me, are on the increase. 



The specimen is singularly intermediate between the two parent 

 forms, as will appear from the following description : — 



The body is somewhat elevated, its depth being two sevenths of 

 the total length, without caudal (rut.) ; the abdomen compressed 

 into a ridge between the ventral fius and the vent, the posterior 

 scales not crossing to the other side of the ridge (alb.). The head 

 is small, contained 4g times in the total length, without caudal 

 {alb.) ; snout short, rather shorter than the eye (rut.), but with the 

 lower jaw distinctly projecting (alb.). Pharyngeal teeth in a 

 single series (rut., alb.) ; gill-rakers very short (rut.). Lateral 

 line running di»tii;ctly below the median line of the tail (alb.), 

 formed by 44 scales (rut.). Transverse line 8/5 ; three series of 

 scales between the lateral line and the ventrals (rut., alb.). 

 Dorsal fin 12-rayed, with its origin a little behind the root of the 

 ventrals, and terminating in advance of the first anal ray (rut.). 

 Anal fin with 16 rays (alb.). Coloration silvery, but less intense 

 than in the Bleak ; back greenish ; and no reddish tinge on any of the 

 fins (alb.). 



2. On LiCHiA VADiGO, Risso. (Plate IV.) 



Of the pelagic genus Lichia only three species are well known 

 and sufficiently characterized, and all seem to be confined to the 

 western parts of the Atlantic. Lichia glauca, the most common, has 

 appeared in a few instances on the south coast of England, whilst 

 the species to which I draw attention now is so scarce that Cuvier 

 knew of two examples only, from the INIediterranean, and that the 

 British Museum possesses only one specimen, 2/ inches long, which 

 was obtained by the late Rev. R. T. Lowe at Madeira. 



On September 17th of last year Captain Macdonald secured 

 another specimen, 20 inches long, of the present species. It was 

 taken in a drift of herring-nets off Wateriiish Point, Isle of Skye, and 



