18/6.] MR. H. SAUNDERS ON THE STERCORARIINifi. 323 



found, so far as I am aware, on the western side of the Straits of 

 Magellan, or on the coasts of Chili or Peru, where its place is taken 

 by a bird which I consider fully entitled to specific rank, and which, 

 strange to say, has all its affinities with the northern Skua, 5. catav 

 rhactes. 



Stercorarius chilensis (Plate XXIV.). 



Lestris antarcticus, var. b. chilensis, Bp. Consp. Av. ii. p. 207 

 (1857) ; (Mus. berol. ex Am. Merid. Rostro vix breviore quam in 

 Europseo, potius graciliore quam robustiore). 



Lestris antarctlca, Scl. & Salvin, Ibis, 1869, p. 284 (Santa Mag- 

 dalena, Straits of Magellan — Cimninghani). 



S. supra fuliginoso-nigricans , pileo summo fere concolori ; corpore 

 reliquo superiore macuUs longitudinalibus rufescentibus versus 

 apicem angustioribus plus minusve dilatatis variegato ; collo pos- 

 tico albicante vix rufescente longitudinaliter striata ; alls dorso con- 

 coloribus, reinignm scapis albis, tectricibus alarum minimis dorso 

 concoloribus et in eodem more rufo maculatis : primariis vix al- 

 bido, secundariis maculis magnis rufescentibus terminatis ; supra- 

 caudalibus rufo marmoratis et subterminaliter maculatis ; cauda 

 nigra, pallidivs terminata ; loris et plumis subocularibus fuligi- 

 nosis pileo concoloribus, his rufo lavatis ; genis, regione parotica, 

 et cm-pore subtus toto cinnamomeo-rujis ; axillaribus et tectricibus 

 subalaribus castaneo-rufis, his et pectoris lateribus paullo fuligi- 

 noso striatis ; colli lateribus dorso concoloribus ; ala subtus tii- 

 gricante, primariis basin versus albis ; rostro nigra ; pedibus nigris. 

 Affinis S. catarrhacti, sed rostra graciliore, corpore subtus con- 

 spicue cinnamomeo-rufescenfe, et subalaribus et axillaribus casta- 

 neis distinguendus. 

 Professor Peters, of Berlin, to whom I wrote on the subject, has 

 courteously informed me that the type specimen in that museum has 

 all the above characteristics. It is a slightly immature bird, and 

 came from Chili. 



Through the kindness of Mr. G. Fanshawe, F.Z.S., I have lately 

 become possessed of four specimens of a Skua shot by his nephew, 

 Mr. J. R. Denison, at Mejillones, on the little strip of coast which 

 belongs to Bolivia, in lat. 23° 5' S., at the end of February or be- 

 ginning of March. Three of these birds are adults ; the fourth is 

 evidently immature, as shown by the brown crescentic tips to the dor- 

 sal feathers ; and the rufous of the underparts is less strongly marked 

 than in the adults, showing that the ruddy colour increases with age. 

 But even the young bird is ruddier than any S. catarrhactes I ever 

 saw. In the museum at Cambridge is a similar immature specimen 

 obtained by Dr. Cunningham, late of H.M.S. ' Nassau,' in the Straits 

 of Magellan, in April ; and Mr. Gervase Mathew, R.N., writes to me 

 that he observed this chestnut-breasted bird at Valparaiso in January, 

 and a month later at Coquimbo, when in H.M.S. ' Resolute,' More 

 than this is not known to me at present ; and in the absence of any 

 reliable information as to its breeding-haunts it would be rash to in- 

 dulge in any speculations as to whether they are to the north or to 



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