42 THE ZOOLOGIST. 



foot apart all over it. How would that work out ? Then add 

 those sitting thickly on the sea just below, those underground, 

 and those coming and going, and this would be only a small 

 part of the whole of the Puffins on that island. There are also 

 great numbers on the western island. There are thousands of 

 Puffins on Ynys Gwylan fawr. On the north-west side they sat 

 as thickly as they do on St. Tudwal's, but the island is much 

 smaller ; still they form a big colony. On Ynys Gwylan fach 

 there is a fairly large number ; but I do not think they like this 

 island, because the thick growth of scurvy-grass keeps the peaty 

 soil very cold and damp, even in a dry season. I found this 

 year that Puffins breed on the mainland between Trwyn-y- 

 Penrhyn and Ogof Lwyd, where the cliff-top is covered with 

 short turf and sea-pink. They nest in old rabbit-holes in the 

 slope or in the earth bank raised along the edge of the cliff ; the 

 holes seemed to be of great depth. Others went into holes part 

 of the way down the cliff. The birds were much more shy than 

 those on the islands, and had I not been attracted by the peculiar 

 sour smell of a warren and the wash and bits of small fish lying 

 about I might have overlooked the fact that they were breeding. 

 I soon noticed some loaded birds flying along the cliff, and then 

 out in wide circles over the sea, and then coming in again. I 

 had to go away to a little distance before I could watch the birds 

 in. About fifty birds sat in a cluster on the sea down below, 

 and there were a few others scattered about. I extracted some 

 young from holes on the islands as big as or rather bigger than 

 a Swan's egg. This was including the down, which stands 

 straight up, and is an inch and a half long or more in places. 

 At this stage the head and upper neck and throat are nearly 

 black ; body dull blackish grey ; belly patch pure white ; be- 

 tween the throat and the white of the belly a band of lighter 

 grey ; bill dull lead-grey ; feet dark pinkish grey. Another 

 rather larger bird, with wing-quills just appearing, had the 

 mantle greyer. The young are active on their feet, and always 

 sought cover. They ran in under us when we were stooping 

 down, and when put at the entrance of the holes ran in like 

 rats. When handled the young frequently uttered a piping 

 "jerp." The nests, when there was any nest, were chiefly 

 formed of coarse grass, grass-roots, and some old quills. Some 



