476 Messrs. Sclater and Finsch's Index to the 



5. Zur Fortpfanzungsgeschichte unseres Kukuks. Zool. Gart. 

 1872, pp. '241-243. 



Relates rather to the eggs of Molothrus sericeus than to 

 those of the Cuckoo. 



6. Fiinf neue Burger von Halle. Zool. Gart. 1872, pp. 

 270-276. 



Pernis apivorus, Turdus pilaris, Emberiza hortulana, Mus- 

 cicapa atricapilla, and M. albicotlis are given as birds breed- 

 ing near Halle. 



Ridgway, R. 



1 . On the Relation between Colour and Geographical Distri- 

 bution in Birds, as exhibited in Melanism and Hyper- 

 chromism. Am. J. Sc. ser. 3. iv. pp. 454-460. 



The author maintains that the two chief modifications of 

 colour met with in North America in the case of widely dis- 

 tributed species are: — (1) a melanistic tendency, and (2) a 

 greater brightness or increased prevalence of the three pri- 

 mary colours. Examples are given of the operation of these 

 laws, as shown by the modifications in colour of the species 

 of Chrysomitris, Myiarchus, Geothlypis, Cardinalis, Carpo- 

 dacus, Cyanura, &c. 



2. Relationship of the American White-fronted Owl. Am. 

 Nat. 1872. pp. 283-285. 



Mr. Ridgway controverts Mr. Elliot's conclusions (Ibis, 

 1872, p. 50) that Nyctale albifrons sive kirtlandi is the young 

 of Nyctale tengmalmi, and that the latter is not distinguish- 

 able from N. richardsoni. He shows that the first-mentioned 

 bird is the young of Nyctale acadica, a much smaller species, 

 and separates the two last-mentioned birds as geographical 

 varieties. 



RlEDEL, T. G. F. 



Letter from, containing Remarks on the True Locality of 



TaDysiptera riedeli. P. Z. S. 1872, p. 1. 

 The correct locality is " Kordo," an island in the Bay of 

 Geelvink. 



RlVA FU RODOLFO, ANTONIO. 



Rapporto sopra una Sylvia rarissima, presa nel circondario 

 di Lugano. Atti Soc. Ital. xv. pp.' 106-108 (1872). 



