36 Mr. H. Seebohm on the 



The femoro-caudal and semitendinosus muscles are always 

 present, but the ambiens and accessory femoro-caudal are 

 always absent. The accessory semitendinosus is nearly 

 always present, but is absent in some of the Picidae. 



The Galbulidae and the Bucconidae have caeca and a nude 

 oil-gland. The Rhamphastidae, the Capitonidae, and the 

 Indicatoridae have no caeca and a tufted oil-gland. The 

 Picidae have also a tufted oil-gland, and the caeca are either 

 absent or only rudimentary. 



In the arrangement of their feather-tracts these families 

 do not differ very much from each other. In none of them 

 is there an interscapular fork to the spinal tract, as there is 

 in Upupa; but in all of them there is a post-scapular bare 

 spinal space, as in Eurylcemus and Hirundo. In the Indicato- 

 ridae, the Galbulidse, and the Bucconidse the spinal tract passes 

 between the scapulars and then divides into two branches, 

 one of which passes on each side of this bare space ; but in the 

 Picidae, the Rhamphastidae, and the Capitonidae this fork is 

 omitted, and the spinal tract suddenly ends in a bare dorsal 

 space. The arrangement of the feather-tracts on the rump 

 varies, but that on the underparts is remarkably constant. 

 There are two distinct feather-tracts on each side of the 

 breast, coalescing on the shoulder (as in Upupa), except in 

 the Galbulidae, where they coalesce along the whole line. 

 The Galbulidae are also abnormal in having a transverse 

 clavicular feather-tract on each side of the breast. 



From these characters the suborder Scansores and the six 

 families it contains may be diagnosed as follows : — 



1. The fourth digit is reversed. 



2. The front plantar leads to the third digit only. 

 The Scansores may be subdivided into two groups : — 



A. Passerine Scansores, with caeca and with a nude oil-gland. 



Bucconidce : vomer absent ; a clavicular feather-tract on 

 each side of breast. 



Galbulidae : vomer present ; no clavicular feather-tract on 

 each side of breast. 





