126 BIRDS OF THE COMMANDER ISLANDS. 



36 (11). Arenaria interpres (Lix.) 102. 



Very numerous in .s])ring and autumn, only a few remaining over sum- 

 mer on Bering Island, where they possibly breed. 



37 (42). Charadrius squatarola (,Lix.) 103. 



Visits the islands on the fall migration. Mr. Grebuitzki has kindly 

 forwarded a specimen ( S ) from Bering Island collected October 8, 1884 

 (U. S. Xat. Mus., No. 10CG13). This species was not obtained by Dr. 

 Dybowski's collectors. 



38 (43). Charadrius domuiicus fulvus (Gm.) 104. 



Regular, though not very numerous on the migrations, spring and fall. 

 Xot known to breed on the islands. 



39 (44). ^gialitis mongola (Pall.) 105. 



A common breeding bird on both islands, appearing during the first 

 half of May and returning south about the end of September. 



Dr. Wilh. Blasius has recently (Zeitschr. Ges. Ornith., Ill, 1886, pp. 

 148-152) discussed the status of the present species with regard to the 

 alleged u3^. inirrhotliorax, and on the strength of six unsexed specimens 

 he thinks it probable that the latter forms at least a "constant variety." 

 The chief characters by which tlie tAVO forms are said to be distinguished 

 consist in difierence in the facial markings, the color of the crown and 

 hind neck, and the length of wing and of tarsus. 



In addition to the twelve specimens which I collected in the Com- 

 mander Islands, I have before me two specimens from Middle Japan and 

 one from the Kurile Islands. Kearly all the specimens are carefully 

 sexed and^ full data given. An inspection of this material may throw 

 some light on the question. 



In the first place it may be necessary to determine whether our birds 

 really are Pallas's Charadrius mongolus. In his Zoographia, II, page 

 137, he describes the head markings as follows: "Frons nigra, ad ros- 

 trum alba, nigraque liuea divisa. Vertex cinereus. Fascia nigra arostro 

 sub oculis coutinua, arcu integro cingit gulam albam." This description 

 suits the male specimen from Bering Island, which we have figured 

 (pi. vii, U. S. Kat. Mus. No. 89051). It still better fits No. 92778, $ , 

 also from Bering Island, and No. 95940, from the Kuriles, for in both 

 there is the black line dividing the white of the forehead (frons)* com- 

 plete above. He further says : "Cervix exsolete ferruginea, intense, et 

 cum fulvedine, collum jugulumque," a feature which we find in all the 

 male birds before us, including the three just mentioned, though of vary- 

 ing extent and intensity. 



Inasmuch as a totally or almost totally black forehead is said to be a 



*Dr. Blasms (o^;. cit., p. 151) evidently misunderstands the English word "fore- 

 head." He says: " Schreuck soil ferner nach Harting ein Exemplar viit schwarzem 

 Vorderkopf vom Amur beschreiben, was in diesem Zttsammenhanfje offenbar 'sckwarze 

 Stirn ' unA Hinneiguug zur FiLrbung von pyrrhothorax bedeitten soil." "Forehead," 

 however, is equivalent to "Stirn" (/rows), but not at all to the German "Vorderkopf." 



