1908. J ox A MALFORMED PLAICE. 161 



March 17, 1908. 



Dr. Hexry Woodward, F.R.S., Vice-President, 

 in the Chair. 



The Secretary read the following report on the additions made 

 to the Society's Menagerie during the month of February 

 1908:— 



The number of registered additions to the Society's Menagerie 

 during the month of February was 171. Of these 146 were 

 acquired by presentation and 7 purchased, 9 were received on 

 deposit and 9 by exchange. 



The number of departures during the same period, by death 

 and removals, was 189. 



Among the additions special attention may be directed to : — 



One male Orang Utan {Simla satijrm), from Deli, Sumatra, 

 presented by Dr. J. C. Gx-aham on Feb. 5th. 



A male and two female Pronghorn Antelopes {Aniilocapra 

 americana), from North America, presented by President Roose- 

 velt on Feb. 4th. 



A Pallas's Cat {Fells manul), from Tibet, deposited on Feb. 29th. 



A Yariegated Spider-Monkey (.l^e/es mrie(/«i5«s), a Red Brocket 

 {Carlacus rufm), and a collection of 63 Birds, including one 

 Scarlet Cardinal {Cardincdls jyhceniceus), four Desmarest's Green 

 Tanagers {Calliste desmaresti), two Olive Saltators {Saltator 

 ollvascens), and five Sonini's Colins {Eapsychortyx sonlni), new to 

 the Collection, from Venezuela, presented by A. Pam, Esq., F.Z.S. 



Mr. G. A. Boulenger, F.R.S., V.P.Z.S., exhibited a remarkably 

 malformed Plaice {Plearonecles platessa) from the London market, 

 which had been presented by the Secretary of the Fishmongers' 

 Company, Mr. J. Wrench-Towse, to the British Museum. 



The fish measures 375 millim. from the end of the snout to the 

 end of the caudal fin, and for the first 245 millim. of its length is 

 perfectly normal in form, scaling, fins, and coloration. But after 

 that a sudden change takes place. The point where the chano-e 

 takes place is indicated on the eyed or coloured side by a rather 

 deep chink in the dorsal and ventral (or left and right) outlines, 

 a,ccompanied by a sudden rise in the length of the dorsal and anal 

 rays, which at that point are separated by a wider membrane ; 

 after this, however, the rays gradually decrease again in length 

 towards the caudal peduncle, which, as well as the caudal fin, is 

 perfectly normal. There is no solution of continuity in the 

 arrangement of the scales or in the course of the lateral line. The 

 only other difference, on this side, from a normal specimen, is a 

 slight raising, like a median swelling, of the vertebral region 

 immediately preceding the caudal peduncle. 



On the blind side, the aberrant aspect is much more striking. 

 At the point mentioned, I. e. 50 millim. in advance of the caudal 



11* 



