.506 PLINY'S NATURAL HISTOET. [Book X. 



RETIREMENT THE TURTLE-DOVE AND THE RING-DOVE THE 



FLIGHT OF STARLINGS AND SWALLOWS. 



In a similar manner also, the blackbird, the thrush, and the' 

 starling take their departure to neighbouring countries ; but 

 they do not lose their feathers, nor yet conceal themselves, as 

 they are often to be seen in places where they seek their food 

 during the winter : hence it is that in winter, more especially, 

 the thrush is so often to be seen in Germany. It is, however, 

 a well-ascertained fact, that the turtle-dove conceals itself, and 

 loses its feathers. The ring-dove, also, takes its departure : 

 and with these too, it is a matter of doubt whither they go. 

 It is a peculiarity of the starling to fly in troops, as it were, 

 and then to wheel round in a globular mass like a ball, the 

 central troop acting as a pivot for the rest. Swallows are the 

 only birds that have a sinuous flight of remarkable velocity ; 

 for which reason it is that they are not exposed to the attacks 

 of other birds of prey : these too, in fine, are the only birds that 

 take their food solely on the wing. 



CHAP. 36. (25.) BIRDS WHICH REMAIN WITH US THROUGHOUT 



THE YEAR ; BIRDS WHICH REMAIN WITH US ONLY SIX OR 

 THREE MONTHS ; WIT WALLS AND HOOPOES. 



The time during which birds show themselves diners very 

 considerably. Some remain with us all the year round, the 

 pigeon, for instance ; some for six months, such as the swallow ; 

 and some, again, for three months only, as the thrush, the turtle- 

 dove, and those which take their departure the moment they 

 have reared their young, the witwall 13 and the hoopoe, for 

 instance. 



CHAP. 37. ,(26.) THE MEMNONIDES. 



There are some authors who say that every year certain 

 birds 14 fly from Ethiopia to Ilium, and have a combat at the 

 tomb of Memnon there ; from which circumstance they have 

 received from them the name of Memnonides, or birds of 

 Memnon. Cremutius states it also as a fact, ascertained by 



13 Galgulus. 



14 Cuvier suggests, that these birds may have been the Tringa pugnax 

 of Linnaeus and Buffon, the males of which engage in most bloody combats 

 with each other on the banks of rivers, in spring. 



