1893.] MR. p. L. SCLATER OX A RARE ARGENTINE BIRD. 167 



' Catalogue o£ Birds in the British Museum,' iu wliieh all reference 

 to Pacliyrliamphas alhinuclia was unaccouutahly omitted. 



In 1891 Mr. Eidgway discovered a specimen of Pachi/rhamjjJius 

 albinucJia, received from Dr. Burmeister himself, among the trea- 

 suies of the U. S. National Museum, where it had lain unnoticed for 

 17 years, and gave an excellent account of it in the ' Proceedings 

 of the U. S. National Museum,' no. 870, which, according to the list 

 of the " dates of pubhcation " printed along with the " Contents," 

 was published on Oct. 22nd of that year. Mr. Itidgway pointed 

 out that the bird is not a true Pachi/rhanqihus, and instituted a 

 new genus, " Xenopsarls" for its reception, referring it to the 

 subfamily Lipauginae of the Cotingidae. 



At about the same date as the rediscovery of this little bird at 

 Washington, an example of it, transmitted by Herr Fritz 8chulz, 

 appears to have reached another centre of ornithological work, 

 Eerlin, and to have attracted Dr. Cabanis's attention. Dr. Cabauis 

 also recognized the necessity of separating this form from Pachy- 

 rhamphus, and referred it to a new genus of Tyraunidse, " Pros- 

 poietus" to be placed near SerpliopluKja. 



On reading these two notices, and knowing that there was no 

 specimen of this peculiar bird in this country, I wrote to Dr. Carlos 

 Berg, who had succeeded Dr. Burmeister in the Directorship of 

 the iS"ational Museum of Buenos Ayres, and asked him to procure 

 me some examples of it. This, in reply, he kindly promised to do 

 if possible, and in the meantime sends for examination one of the 

 typical specimens belonging to the Museum of Buenos Ayres, which 

 I have now the pleasure of exhibiting. As regards the systematic 

 position of this form I agree very nearly with Mr. Eidgway, and, 

 in order to render the subject complete, I append to these remarks 

 his generic and specific characters of this little-known bird very 

 slightly modified. 



Grenus Xenopsaris. 



Xenopsaris, Eidgway, Bull. U. S. X. Mus. xiv. p. 479 (Oct. 1891). 

 Prospoietus, Cab. Bericht orn. Gresellsch. Berlin, ix. p. 4 (Nov. 

 1891). 



Char. gen. Similar to Casiornis, Bp., but bill very much smaller, 

 narrower, and more elevated at the base, with culmen gradually 

 curved throughout its length ; nasal and rictal bristles much less 

 developed ; tail nearly as long as the wing, emarginate and rounded 

 (i. e. double-rounded), the feathers rather narrow ; primaries 

 exceeding secondaries by more than length of biU; the second, 

 third, and fourth quills nearly equal and longest: first primary 

 equal to sixth ; tarsus about equal to length of bill measured from 

 the rictus ; middle toe considerably shorter than tarsus (slight!}' 

 less than exposed culmen) ; feathers of pileum lengthened and 

 broad, forming, when erected, a full rounded crest ; along each 

 side of the lower back and rump a conspicuous tuft of pure white 

 cottony feathers. Colour (both sexes) gi-eyish above, with glossy 



