BREEDING HABITS OF THE PURPLE HERON. 409 



Purple Heron, quote the account by Lieut. -Col. Irby of his visit 

 to a colony in the south of Spain. It is interesting to learn that 

 the latter ornithologist only found three or four eggs in each nest, 

 in the place of five or six in rny own experience. Abundance of 

 food may perhaps account for the greater fecundity of the Herons 

 I came into contact with, for Dresser states that the Purple 

 Heron is said to devour large numbers of young Green Frogs 

 (Rana esculenta). Now these creatures abound in the large ponds 

 before mentioned, and the Herons must have no difficulty in 

 eating their fill throughout the nesting season. Some divergence 

 of opinion may be noted on the dimensions of the eggs of the 

 present species. Seebohm states that they are indistinguishable 

 from those of A. cinerea, except that they are slightly smaller. 

 He gives the following measurements : length 2*45 to 1*95 in. 

 by 175 to 1*45 in. in breadth. Dresser states that eggs taken in 

 Hungary varied from 2 T 4 o X 1 f# to 2i§ X lf£ in. The average 

 dimensions of eggs of A. cinerea the latter author gives as 2| X 

 \i& in. Saunders, in his ' Manual of British Birds,' states that 

 average eggs of A. purpurea measure 2*2 X 1*5 in. These dimen- 

 sions I find approximate to the sizes of the eggs I took in France; 

 my largest specimen being equal to 2'23 in. in length by 1*62 in. 

 in breadth, and my smallest but 195 X 1*47 in. An attenuated 

 egg, however, has a length of 2*30, but a breadth of only 1*50 in. 

 Comparing these measurements with those of eggs of A. 

 cinerea kindly supplied me by Mr. E. J. Ussher, who has had 

 considerable experience with the latter species in Ireland, I think 

 it may be laid down as a general rule that large eggs of A. pur- 

 purea in size rarely overlap those of small ones of A. cinerea. 

 According to the above-named ornithologist, eggs of A. cinerea 

 vary between 2"6S X 1*71 in. and 2*39 X 1*7 in. These dimensions, 

 I may say, tally with those of eggs in my own collection. 



