242 The Common Raven 
things in the Island of Crete, where, out of many nests visited, only 
one contained eggs during the last week of March 1886, the rest 
being still in course of construction. Why it is that in the exposed 
and almost arctic climate of northern Scotland as well as in the wet 
and storm-swept shores of Ireland and the west of England these 
birds should eject to lay in February and why in sunny Andalucia 
they should defer doing so till the middle of April is, to me, an 
insoluble problem. Yet again, as to the number of eggs laid, 
whereas in our Islands, three or four would seem to be the usual 
complement, in Spain, six is the number commonly found and 
next to that five. 
Another puzzling habit of Ravens in Andalucia is the manner 
in which they, from time to time, collect in considerable numbers 
for a brief period and then as suddenly disperse. On such 
occasions they are invariably in pairs and their movements are 
obviously made in accordance with some well-defined ulterior 
object. What this can be, I am unable to say, for in all my 
wanderings in wild Spain I have never met with a large party 
of Ravens collected around the carcass of an animal, nor have 
I ever heard of such a gathering. I mention this, because, when 
Vultures are seen to be moving towards any defined point, it 1s 
invariably to foregather at one of their banquets. 
To give an example of these assemblages of the Common 
Raven. On 18 April, 1906, | was riding along an open river 
valley and noticed a pair of Ravens, coming from the north, settle 
on a pine tree to my front. Soon a second pair arrived from the 
same direction followed by another and yet another. Meanwhile 
the first arrivals had moved on and disappeared through a pine- 
wood out of sight and were in turn followed by their friends. 
Before I had passed this line of flight, no less than seventeen 
pairs of Ravens had proceeded along it. Now what could these 
birds have had in view? Although Ravens are numerous in these 
