1896.] NATURAL SCIENCES OF PHILADELPHIA. Ill 



males and females of the same species differ greatly in this 

 respect when the nuptial plumage of the adult male is highly 

 developed as compared with that of the female or with its own 

 winter plumage. 



III. The amount of change effected in the plumage at any partic- 

 ular molt varies considerably in different individuals of the 

 same species and sex. 



IV. Some species which have a well marked spring molt in their 

 first and second yeard may discontinue it afterwards, when the 

 adult plumage has once been acquired. And, on the other 

 hand, some individuals may continue to molt in the spring, 

 while otliers of the same species cease to do so. 



V. The remiges are molted less frequently than any other part of 

 the plumage. As a rule, they are only renewed at the annual 

 molt (exception Dolichonyx). 

 VI. Variability in the order of molt in the remiges and presence or 

 absence of molt in the flight feathers at the end of the first 

 summer are generally family characters i. e., Ceryle differs from 

 any other species treated of in this paper in the order of molt in 

 the primaries. All Picidse and all Icterid?e except Icterus, (and 

 Dolichonyx'^) molt the flight feathers with the rest of the first 

 plumage. None of the Oscines except IcteridjB (as above), some 

 (all?) Hirundinidse, Otocoris and Cardinalis molt the flight 

 feathers at this time. 

 Some other exceptions to the above statements no doubt occur, 

 but they cover the vast majority of cases. 



In connection with the second statement attention should be called 

 to Ammodramus sandwichensis savanna which has practically the same 

 plumage at all seasons, but which has an extensive molt of the body 

 plumage in spring. 3Ielospiza fasciata, which closely resembles it in 

 plumage at all seasons, has scarcely a trace of spring molt. Avww- 

 dramus caudacntus is the only other species that shows any consider- 

 able spring molt, and in which the sexes are not strikingly different. 

 As stated above, the number and extent of the molts do not of 

 necessity bear any relation to the systematic position of the species. 

 The Friugillidse include species which exhibit the simplest series of 

 molts as well as some examples of the most complicated molting 

 known among the Passeres. The species of certain families do show 

 practical uniformity in their molts, but in such cases there is also 

 uniformity in the relative development of plumage of the sexes. 



