Toucans and other Picarians. 103 



Short-billed Toucan (Rhamphastos brevicarinatus). 



The female is smaller than the male ; her bill is considerably- 

 shorter, with the culmen (ridge) more arched, but the terminal 

 hook shorter and more abruptly formed. 



Doubtful Toucan [Rhamphastos tocard). 



I could not discover any examples with the female sex-mark in 

 the series at the Natural History Museum ; but I have little doubt 

 that the smaller birds, with much shorter and less tapering bills, 

 represent that sex. 



Red-billed Toucan (Rhamphastos erythrorhijnchus). 



The female is smaller than the male, and her bill is distinctly 

 shorter and less curved at the tip. 



Cuvier's Toucan (Rhamphastos cuvieri). 



In the Museum series of skins I could discover no example with 

 the female sex-mark; but this species is certain to differ sexually in 

 the same manner as its allies. 



Ariel Toucan (Rhamphastos ariel). 



In the female the bill is slightly shorter than in the male, with 

 shorter terminal curvature. In the specimens which I compared, 

 the flattened basal portion of the culmen was twice as wide in the 

 female as in the male. I am, however, doubtful as to the value of 

 this as a distinctive character ; it seems possible that it may be 

 merely an indication of age. With a large series of sexed specimens 

 alone could one definitely decide upon the constancy of a character 

 of this nature. 



Sulphur-and- White-breasted Toucan (Rhamphastos vitellinus). 



The female is smaller than the male, and has a considerably 

 shorter bill. 



Green-billed Toucan (Rhamphastos dicolorus). 



By a comparison of specimens labelled as male and female in the 

 Museum series, one is forced to the conclusion that the usual sexual 

 differences in the structure of the bill are reversed in this species. 



Maximilian's Aracari (Pteroglossus wiedi). 



The female is a little smaller than the male, and has a rather 

 smaller bill. I noted also that the blackish dorsal stripe on the 

 culmen of the bill was wider, especially towards the base, in the 

 female ; but whether this is a fairly constant character or not can 

 only be satisfactorily settled by a comparison of many sexed 

 examples. 



