1878.] PROF. A. H. GARROD ON INDICATOR MAJOR. 931 



Pterylosis. — This has been recorded by Nitzsch in his ' Pterylo- 

 graphy ;' and it seems more than strange that the characteristically 

 Picine distribution of its feather-tracts did not lead that able orni- 

 thologist to recognize its true relationships. He retained it among 

 the Cuculidse. 



My study of Pterylography has led me to look upon the nature 

 of the dorsal tract as all-important in determining to which great 

 group of Birds, the Homalogonatse or Anomalogonatse 1 , any 

 doubtful family belongs. When the dorsal tract develops a fork 

 between the shoulder-blades a bird is homalogonatous ; when the tract 

 runs on unenlarged to near the lower ends of the scapulae, then it is 

 anomalogonatous. Again, among the Anomologonatse, when the 

 pectoral tract bifurcates into an outer and an inner branch just after 

 commencing on the chest, then the bird is one of the Piciformes, 

 and has a tufted oil-gland ; when the pectoral tract does not bi- 

 furcate at all, or only at the lower end of its pectoral portion, but is 

 only increased in breadth instead, theu the bird is Passeriform 2 , 

 and has a naked oil-gland. Exceptions to these rules scarcely 

 exist. 



In that the dorsal tract of Indicator does not form a fork, but 

 remains narrow, between the shoulder-blades, it is anomalogonatous 

 — the Cuculidse being homalogonatous ; in that it possesses a free 

 outer pectoral band to the anterior tract, it is a Piciform bird. The 

 oil-gland is also tufted. 



A careful examination of the skin proves that the genus agrees 

 more closely in its feather-tracts with the Picidae, Capitonidse, and 

 Ramphastidae than Nitzsch's figures would tend to prove. To me it 

 is evident that there is a communication between the thoracic ex- 

 tremity of the inferior neck-tract and the upper extremity of the 

 humeral tract, as in the Picidee, Capitonidse, and Ramphastidae. 

 Again, in the three groups just named there is a great weakness or 

 an entire disappearance for a short distance of the dorsal tract 

 towards the lower extremity of the interscapular region. In Indi- 

 cator this same weakness exists ; so that, with the exception of a 

 single feather in the middle line, the appearance of the region in 

 question is much more like the arrangement in Ramphastos than in 

 Nitzsch's figure of tbe genus. On the ventral surface of the fleshy 

 tail I find a median subcircular space surrounded by feathers, as in 

 the Picidae and Ramphastidae, as well as in the Capitonidse appa- 

 rently. The caudal termination of the dorsal tract agrees with the 

 account given by Nitzsch. I could find no trace of a duplication 

 of the lumbar tract. In the possession of twelve rectrices Indicator 

 differs from the Capitonidse and Ramphastidae, which have ten, 

 like the Picidse. 



Skeleton. — The specimen of the skull of Indicator examined by 

 Professor Huxley 3 at Mr. Sclater's request was too imperfect for 

 exact description. The considerable interval between the maxillo- 

 palatines is recorded by him. I am now able to add that the vomer 



1 Vide P. Z. S. 1874, p. 116, for definition of these terms. 



3 Vide P. Z. S. 1874, p. 119. 3 Ibis, 1870, p. 170. 



