oli Mr. P. L. Sclater on the Geographical 



In Manucodia atra the tracliea forms only " a short loop 

 lying on the interclavicular air-cell, between the rami of the 

 furcula, much as in many specimens of the genus CraxP In 

 Manucodia chalybeata and M. jobiensis the loop extends about 

 two thirds down the surface of the pectoral muscles. 



Manucodia comrii (fig. 2, p. 513) has a much more extensive 

 loop than any other species : in the specimen before me the 

 two sections of the trachea which form the loop run closely 

 adherent to each other in a slightly sinuous course to the left of 

 the sternal keel ; they are directed beyond the pectoral muscles 

 somewhat obliquely, and finally end on the right side of the 

 body in the immediate neighbourhood of the cloaca, slightly 

 overlapping the posterior border of the thigh-muscles. The 

 accompanying figure, which is of natural size, will give a 

 correct idea of the course of the loop. 



The bird proved on dissection to be a male. 



The species Manucodia comrii was described some years 

 ago* by Mr. Sclater as '' the finest and largest " of the genus ; 

 the bill is longer and the curling of the feathers of the head 

 is carried to a greater extent. It is interesting to find the 

 tracheal loop also showing a more pronounced character than 

 in other species. 



XLIII. — On Recent Advances in our Knowledge of the Geo- 

 graphical Distribution of Birds. By the Editor f. 



It is now nearly thirty-four years ago since I read before the 

 Linnean Society of London a memoir on the geographical 

 distribution of the Class of Birds (1)|, in which, after a pre- 

 liminary discussion upon the subject, I pointed out what I 

 considered to be a most natural way of dividing the earth's 

 surface, looking only to the distribution of the families, 



* " On the Birds collected by Dr. Comrie on the South-east Coast of 

 New Guinea during the Siu-vey of II.M.S. ' Basilisk,' " P. Z. S. 187G, 

 p. 459. 



t Slightly modified from an Address to the Second international 

 Ornithological Congress at Budapest in May 1891. 



I The numbers in brackets refer to the titles of works given in the 

 Appendix, pp. o48-o;"J7. 



