124 PROCEEDINGS OF THE ACADEMY OP 



Family LARIDyE. 

 Subfamily LESTRIDIN^, 

 Of this, the first subfamily of the Laridce, there are at present known to 

 exist eight species, belonging to two genera. Of these, five inhabit the 

 northern, and three the southern hemisphere. The five nortliern species are 

 all represented in North America. The following analytical table will represent 

 the characters of the species and genera sulficiently well for our present 

 purposes. The diagnoses are purposely made as brief as possible, only the 

 most prominent features being noticed. 



§ Analytical Table of the Genera and Species of the Lestridince. 



I. Statura maximi, et forma robustissimi. Pedes et rostrum 

 validi. Tarsus brevior quam digitus medius cum ungue. 

 Rectrices medise latsevix ultra cseteras porrectae Genus Buphagus. 



a. Rostri longitude poll. 2, et ultra; altitude "75. Ad 



anguli oris 3*00 poll. Ex maria arctica B. skua. 



h. Rostrum brevius, crassius. Ex maria antarctica B. antarcticus. 



II. Statura minores, et forma graciliores. Pedes et rostrum 

 graciles. Tarsus non brevior quam digitus medius cum 

 ungue. Cauda longior, et rectrices medise valde ultra cseteras 



porrectse Genus Stercorarius. 



1. Tarsi postice asperrimi. Rectrices mediae latae in 

 apices ipsas. 



a. Rectrices medise cseteris 4 pollices longiores S. pornarinus. 



2. Tarsi postice subasperi. Rectrices medise longse, rigi- 

 dse, acuminatse. 



a. Rectrices medise cseteris 4 poll, longiores S. parasiticus. 



b. Similis S. parasitica ; sed major, cauda totd longiore, 



plus rotundata S.Richardsoni. 



c. Similis S. pirasitico ; Bed minor, rostro magis com- 

 presso, rectricibus mediis elongatis, apidb.is rotun- 



datis (Bp.) S. Hardji. 



d. Similis .'?. parasitica. Sed etiam minor S. Buffono ; 

 rectricibus mediis lineari-acutis, rachide denudata 



rigida, pollice et ultra creteras superantibus (Bp.) 5. spinicauda. 



3. Tarsi postice subasperis. Rectrices medise longissimae, 

 flexibiles, filiformes. 



a. Rectrices medise cseteris 8 ad 10 pollices longiores.... iS. Buffoni. 



Genus BUPHAGUS Moehring. 



Buphagus, Moehring, Genera Avium, 1752, page 66, No. 71. Typus Lanis 

 catarracles, Linn. 



Stercorarius, "Brisson," Vieillot, Nouv. Diet. d'Hist. Nat., 1817, 153. Typus 

 idem. (Sed non verus Stercorarius, Briss. cujus typus Larus parasi- 

 ticus, L. est.) Gray, Genera of Birds, 1849, 651. Degland, Ornith. 

 Europ. 1849, ii. 287. Bonaparte, Conspectus Avium, 1856, 206. Law- 

 rence, Gen. Rep. Birds N. A. 1858, 838 ; et aliorum auctorum. 



Catharacta, Briinnich, Orn. Bor. 1764, 32. Typus Cath.skua Briiun. Bona- 

 paite, Comparative List, 1838. 



Larus, (partim) Linnseus, Systema Naturse, 1766. Gmelin, Systema, Natu- 

 rse, 1788. Latham, Index Oruithologicus, 1790. Meyer et Wolf, Tassch- 

 enbuch deutsch. 1810. 



Catarractes, Pallas, Zoog. Rosso-As. 1811, ii. 808. Typus C. skua. Steph- 

 ens, Shaw's Gen. Zool. xiii. 1825, 214. 



Lestris, "lUiger," Temminck, Man. Orn. 1820 — 40. Typus L. catarractes. 

 (Sed non verus Lestris 111. cujus typus L. parasitica L. est.) Faber, 



[May, 



