410 Mr. A. R. Wallace on the Arrangement of the 



when we look to the next series of families, having only 9 

 primaries, we find that there still exists the greatest diversity 

 of opinion as to their true position. Every modern ornitho- 

 logist, without exception, has attempted to intercalate them 

 among the families of the first series, in some cases even in- 

 corporating them into one or other of those families, owing to 

 superficial resemblances. In this series the first of the nine 

 primaries is always fully developed, and often very long ; and 

 this well-marked character is found to group together a set 

 of families which have in many cases acknowledged affinities 

 for each other, but which offer the greatest difficulties when 

 we attempt to locate them naturally among the families of 

 the first series. They have also a well-marked geographical 

 aspect, being as characteristic of the New World as the pre- 

 ceding series is of the Old. Four out of the ten families are 

 exclasively American ; one is peculiar to the Sandwich Islands, 

 and has strong affinities to an American family ; three others 

 are as well represented in America as in the Old World ; 

 while the only one totally absent from America (Dicseidai) is 

 typically Australian — that region which has the most affinity 

 to the Neotropical. I now give a list of these families, and 

 will then briefly remark on their affinities : — 



Series B. Tanayroid Passer es. 



Wing with 9 primaries, the first of which is fully developed and usually 



very long. 



1. Motacillidse. 6. Ampelidae. 



2. Mniotiltidffi. 7. Hirundinidae. 



3. Coerebidse. 8. Tanagridse. 



4. Drepanidse. 9. Fringillidaj. 



5. Dicceidse. 10. Icteridse. 



The Motacillidifi do not come well in series A ; and there has 

 been no general agreement a.s to their location. The Mnio- 

 tiltidse and Coerebidse are so closely allied that good ornitho- 

 logists differ as to where some of the genera (e. g. Dacnis, 

 Certhiola) are to be placed ; yet they cannot be arranged with 

 their supposed allies in the first series without widely sepa- 

 rating them. The DrepauidEe of the Sandwich Islands, very 



