226 TJ. S. NATIONAL MUSEUM BULLETIN 217 



tively. The first egg was thus laid 18 days after the first male was 

 seen and 14 days after yellow warblers became common. 



The excess of weight in females over males may be related to the 

 presence of numerous females with enlarged eggs. In several other 

 species it has been remarked that gravid females are heavier than 

 those not laying. At no time during our observation were any of 

 the species of warblers found to be fat. Of 91 specimens only three, 

 all females, were found to be medium fat. 



These yellow warblers and those from northern Alaska were all 

 consistent with the race amnicola^ which ranges across the continent 

 undifferentiated from Alaska to Labrador. The arctic range, how- 

 ever, is confined to the area west of the Mackenzie River. 



The Indians call this bird Tsetso. 



Dendroica coronata hooveri McGregor 



Males Females 





Weight 



Fat 



TesUs 



Weight 



Fat 



Eggt 



DtOe 



Q>.) 





{mm.) 



(9.) 





(mm.) 



May 20 



12.0 



NF 



4.6x7, 4x4.5 



11.8 



NF 



1 



May 21 



11.8 



NF 



,3x5 









May 24 



13.6 



LF 



6x8, 5x7 









JnneS 



13.0 



LF 



,6x5 









June 4 



13.2 



NF 



6x10, 6x6 









June 28 



14.0 



LF 



6.6x9.5, 8x8 









(Aver.) 12.9 



Frank Williamson heard the first myrtle warbler singing on May 

 18. Between May 20 and 28 an individual or a pair could occasionally 

 be called in the mixed spruce and poplars along the slope of the 

 bluff, but thereafter they were seldom noticed. Williamson found 

 them rather common at Driftwood River, and near Kenneth Nukon's 

 cabin, 15 miles east of Old Crow, there were a few about on June 3, 

 4, and 5. No eggs were found but because of the presence of pairs 

 during the breeding season it is concluded that myrtle warblers 

 were nesting. The Indians call this bird Kyekyszez. 



This northwestern breeding race of myrtle warblers migrates to 

 winter from southern Oregon through the valleys of California (Wet- 

 more, 1926, p. 206) . 



Dendroica striata (Forster) 



Males Females 



Date 



Weight 



(a.) 



Fat 



Testes 

 (mm.) 



May 29 



12.4 



LF 



5x7.5, 6x6 



June 3 



12.1 



NF 



5x9, 6x7 



Junes 



13.7 



LF 



5x7, 





12.6 



LF 



5x7, 4x5 



June 6 



12.6 



LF 



5x9, 5x6 



June 10 



11.4 



NF 



4x6, 4.5x5.6 



June 23 









Weight Fat Eggs 



(a-) 



12. 8 MF 6 heavily in- 



cubated eggs 



