197 
It does not become common in spring until in the latter part of March or first of 
April, and all have retired northward by the end of April. During the fall 
migrations I have first observed it on September 25. 
129. Regulus calendula (Linn.) Ruby-crowned Kinglet. 
An abundant migrant, though hardly so numerous assatrapa. Arrives during 
the fall migrations perhaps a week before satrapa, and I have first noted it during 
the spring migrations on April 12, or about a week after satrapa appears, and it 
vanishes northward by May 1. This is not nearly so hardy a bird as the Golden- 
crowned, and it winters much farther to the southward. 
130. Polioptila cerulea (Linn.) Blue-gray Gnatcatcher. 
An abundant migrant and a rather rare summer resident; appeared this 
season on April 20, and had almost entirely passed on northward by the first of 
May. 
131. Turdus mustelinus (Gmel.) Wood Thrush. 
A rather uncommon summer resident, arriving this season on April 24. 
132. Turdus fuscescens (Steph.) Wilson’s Thrush. 
A moderately common migrant; arrives about first of May. 
133. Turdus alicie (Baird.) Gray-cheeked Thrush. 
An abundant fall migrant; arrives about the middle of September and van- 
ishes southward by the first week in October. I have yet to note it during the 
spring migrations. 
134. Turdus ustalatus swainsonii (Cab.) Olive-backed Thrush. 
A common migrant; more abundant in fall than in spring. This year I first 
noted it on April 23, and during the fall migrations I have first observed it on 
September 7, and it probably vanishes southward by the end of September. 
135. Turdus aonalaschke pallasvi (Cab.) Hermit Thrush. 
An abundant and probably the most abundant thrush during the migrations; 
especially abundant in spring. First appeared this season on April 11, and I last 
saw iton May 18. On its southward flight it arrives during the latter part of Sep- 
tember. 
136. Merula migratoria (Linn.) American Robin. 
An abundant summer resident; sometimes arrives as early as the 14th of Feb- 
ruary, and I have seen one as late as the 15th of December. 
137. Sialia sialis. (Linn). Blue Bird. 
Until within the last two or three years the Blue Bird was a common sum- 
mer resident, but of late it has become almost a rarity. In fact, I failed to find 
