16 FBIENDS OF THE AGRICULTURIST 



The main differences between the two species are as 

 follows : The flanks, which in olivaceus are orange- 

 chestnut, are brown in cabanisi ; the bill of the latter 

 bird is wholly of a yellowish-orange colour, while that 

 of olivaceus has the upper mandible of a dusky olive-green. 

 The Cape Thrush ranges from Cape Colony through 

 Natal to Zululand, while its place is taken in the Orange 

 Kiver Colony, Transvaal and Bechuanaland by the 

 Orange-billed species. 



The Kurrichaine Thrush (T. Ubonianus) is somewhat 

 similar to the two preceding species, differing mainly in 

 having the centre of the belly white and the bill bright 

 orange-red. W. L. Sclater says this is the commonest 

 form of Thrush between the Orange and Zambesi Rivers. 



All three birds lay from three to five bluish-green eggs, 

 speckled and blotched, chiefly at the larger end, with 

 reddish-brown. They build large cup-shaped nests of 

 twigs and roots. They feed largely on insect life, thus 

 being useful birds, but are not above devouring a little 

 fruit occasionally. 



Two fairly common birds in the district of Grahams- 

 town are the Cape Rock-Thrush (Monticola rupestris} 

 and the Sentinel Rock-Thrush (M. explorator). Both 

 are of a reddish-brown colour above and chestnut-red 

 below, the Cape Rock-Thrush differing from its congener 

 in having only the head and neck of a slatey-blue colour, 

 whereas this coloration is continued on to the back in 

 the case of the " Sentinel." In addition, the latter is a 

 smaller bird. The young birds and the females have the 

 head and adjacent regions coloured like the back. 



Both these birds lay eggs of a very pale blue ground 

 colour (almost white), sparsely speckled with pale rusty- 



