986 U.S. NATIONAL MUSEUM BULLETIN 23 7 part 2 



length. In one hour, the parents made five trips to the nest, making 

 a "chittering" noise as they approached the nest. Whether or not 

 this was an alarm reaction to the observer's presence is not known. 

 J. C. Johnson, Jr., (1956) describes the behavior of a pair of Cassin's 

 sparrows at the nest: 



For an hour * * * both remained most of the time along an approximately 

 100-yard stretch of fence. The male sang from posts and wire, never during 

 flight, with sUent periods of up to 20 minutes; its mate spent much of her time 

 on the ground near the fence, occasionally flying for brief visits to a growth 

 of small wild plums about 75 yards to the south. No young birds were in evidence, 

 nor did either adult appear to be visiting a nest. Within half an hour after moving 

 into my car, using it as a "blind," I twice saw the male, with food in its beak, 

 fly directly from one fence post to a particular small area of ground nearby; 

 During the next half hour the female also visited this spot twice with food, though 

 she arrived by a much more devious route. The nest held five nearly-fledged 

 young * * *. 



Plumages. — The natal down is sparse, and very dark. The gape 

 is a dull orange-yellow. Richard R. Graber (1955) describes the 

 Juvenal plumage as follows: "Feathers of forehead and crown blackish 

 brown, edged with light buff (pattern irregular streaking). Nape 

 cream, streaked mth dark brown. Back feathers blackish, edged 

 with cream (scaled pattern). Rump similar but lighter. Longest 

 upper tail coverts black along shaft, edged with light reddish brown. 

 Deck retrices vary from dull gray to light rusty brown (color phases?) ; 

 suggestion of barring from black herringbone pattern along shaft. 

 Other retrices largelj'^ black, narrowly light edged, and marked 

 (ventrally) with dull white, terminally. Primaries edged with white, 

 secondaries and tertials with cinnamon buff. Secondaries edged 

 terminally with white, tertials margined with white. Coverts, like 

 remiges, black. Lessers and gTeaters edged with cinnamon buff, 

 medians and greaters tipped with white (two narrow wing bars). 

 Lores and eyering whitish. Obscure superciliary line, white streaked 

 with black. Side of head tinged with buffy, flecked vnih dark brown. 

 Under parts light cream-colored; chin, throat, breast, sides, and 

 flanks conspicuously streaked wdth black. Belly and crissum un- 

 marked. Crissum more richly colored than other under parts. 

 Leg feathers brown and cream." 



The postjuvenal molt occurs in late fall (Graber, 1953; A. R. 

 Phillips, 1951b). The breast streakings sometimes persist through 

 the first winter to as late as March. 



Robert Ridgway (1901) gives the following description of the adult 

 Cassin's sparrow: 



Adults (sexes alike). — Above light brown, broadly streaked with light gray, the 

 pUeum streaked also with black or dusky; scapulars and interscapulars marked 

 with dusky subterminal spots or bars in a light brown field, the margins of the 



