164 ZOOLOGICAL RESEARCHES 



to St. Thomas and Prince's Island and to the opposite 

 mainland ^). 



Halcyon dryas is according very well with the variety 

 cinereifrons ^ both in size and color, having the same tinge 

 of the blue parts as our specimens from the Senegal. If 

 there is any difference between them, it must be sought 

 for in the color of the crown, which is decidedly more 

 olivaceous in H. dryas than in H. cinereifrons , but , as will 

 be shown directly , this color depends too much on the age , 

 as that it would draw a sufficient limit between them. 



Concerning the color of the crown in H. malimhica , at- 

 tention must be called to the fact that in quite young spe- 

 cimens the crown of the head , except the front , is of a 

 somewhat dull sea-green, passing vdth growing age through 

 olivaceous into dirty gray, but always inclining more or 

 less to olivaceous towards the nape. The crown of our Bis- 

 sao bird cannot be distinguished from that of H. dryas. 



The color of the under surface may also be considered 

 a positive character for the age of these birds. In quite 

 young specimens , the colors underneath are principally the 

 same as in the adult, but more or less covered with an 

 ochraceous buff, occupying even the cheeks and sides of the 

 neck, the sea-green on the breast being much less intense 

 than it is in the adult bird. In more advanced specimens 

 the ochraceous color successively gives way to the color of 

 the adult, beginning in the centre of abdomen and throat, 

 and ending on the sides of the body. The beautiful sea- 

 green seems to proceed successively, aud only occasionally 

 by moulting as is the case with a semi-adult Liberian spe- 

 cimen which shows some splendid new feathers amongst 

 the dull greenish ones. 



The bill in young birds is of a deep orange-red , with 

 but little dark (cherry-brown) marks on the lower mandible. 



1) A specimen from the Senegal, mentioned by Mr. Bouvier (Cat. Geogr. 

 des Ois. recueiilis par Marche et Compiègne, Paris 1875) as H. dryas, will 

 undoubtedly be the Senegal variety of H. malimbica. 



Notes frora tbie Leyden IN^useuin, "Vol. VII. 



