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Show 50 ON FISHES NEW TO THE BRITISH FAUNA. [Feb. 5, 5. Notice of two Pishes new to the British Fauna. By Dr. A. G U N T H E R , F.R.S. [Received February 5, 1889.] (Plate IV.) 1. On a Hybrid between the Roach (Leuciscus rutilus) and the Bleak (Alburnus 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 fins and the vent, the posterior scales not crossing to the other side of the ridge (alb.). The head is small, contained 4j 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 distinctly 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 1 2-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 Mediterranean, and that the British Museum possesses only one specimen, 27 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 Waternish Point, Isle of Skye and |