CORACT^ 205 



Australian. The genera allowed by Debssee in his recent 

 monograph of the family are Coracias, Eurystomus, Brachy- 

 pteracias, Atelornis, and Leptosomus. They are distributed 

 by him in three subfamilies ; the first two genera constitute 

 the first, the next two the second, while Leptosomus is placed 

 in a subfamily by itself. The rollers have an anisodactyle 

 foot; the feathers ha,\e a,n aftershaft ; but the oil gland is 

 nude. The pterylosis has been studied by Nitzsch, Foebes, 

 and by myself.' In Eurystomus orientalis the ventral tracts 

 commence as two from the very first ; at the angle of the 

 mandible they are double. Though Nitzsch has figured 

 the pterylosis of the throat of Coracias garrulus as if it were 

 continuous, I do not find any difference from Eurystomus in 

 this particular. On the breast the two divisions of the 

 ventral tract remain single ; there is hardly a trace of the 

 outer branch. The tracts are here rather wide. The dorsal 

 pterylosis narrows gradually until between the shoulders, 

 where the feathering is very strong, and where it divides 

 into two branches ; these unite again just at the articulation 

 of the femora, and finally terminate a little way in front of 

 the oil gland. 



Leptosomus has a slightly different pterylosis ; the 

 ventral tract is single to about an inch behind the junction 

 of the mandibular rami ; for a considerable distance the 

 ventral band is continuous with the dorsal, so that the 

 lateral neck spaces do not commence until about three- 

 quarters of an inch above the shoulder. About the middle 

 of the sternum the pectoral tract of either side gives off an 

 outer branch some four feathers wide and slightly stronger 

 than the main tract. The two forks of the dorsal tract 

 run in between each other, the narrower posterior portion 

 between the limbs of the wider anterior portion, as is the 

 case with so many birds. Foebes has noted that Atdornis 

 has a pterylosis which agrees with that of Eurystomus, 

 already described. 



Leptosonms differs, however, from the remaining Coraciidse 

 in the possession of powder-down patches, which were first 



' See anatomical preface to Deesseb's monograpli of the group. 



