FREQUENTING HERONSGATE, HERTS. 159 



aberrant beliavioiir on the part of the rook, for it is pre- 

 eminently and inseparably a bird of the soil, and one to which 

 agricnlturo owes much. Before the frost set in, and when the 

 plough was busily at work, a vast assemblage of rooks collected 

 in the fields near here, and I was much impressed by the important 

 help the friendly birds were rendering to the farmer by freeing 

 the ground of harmful grubs. The flock, at a low computation, 

 must have numbered some 500 or 600 individuals, and if we 

 estimate the probable amount of food consumed by each at only 

 half-a-pint a day — and the bird has a very voracious appetite — 

 it becomes evident that the rook is a factor of very considerable 

 importance in the economics of agriculture. So that, under all 

 the circumstances, and although the epithet "■ frugilegus " is not 

 entirely undeserved, I have come to think that a better term 

 might and should be devised for our friend the rook ; because 

 it is very invidious thus to record the fact of his occasional 

 deviations from an ordinarily strict rule of conduct, and ti'uly 

 ungracious to fasten this name upon him, overlooking his claim 

 to acknowledgment for good honest services rendered, and keeping 

 him in our remembrance only as the " fruit-gatherer." 



The Lessee Spotted Woodpecker i^Dendrocopm nmior). — This 

 species is by far the commonest of the three woodpeckers at 

 Heronsgate. It is very diiiicult to approach, and, although 

 fi'equently heard, is not so often to be seen, but this is sometimes 

 to be done by creeping up to the tree. When disturbed it may 

 be observed flying olf to the wood. It seems to have a great 

 partiality for oaks on the outskirts of woods, its preference for 

 those trees being due probably to the fact that the rough bark 

 being full of holes and crevices affords a better return in insect- 

 food than is the case with other ti'ees having smooth bark. 



The Green Woodpecker {^Geciniis viridis). — This species occurs 

 occasionally on the highest ground where the soil is light and 

 sandy, attracted no doubt by the ants' nests, the " eggs" in which 

 form a not inconsiderable part of this woodpecker's diet. Some 

 fragments of the eggs of this species were brought to me for 

 determination last summer, the parent bird having been seen 

 by the ubi([uitous boy to enter a hole in a birch tree, whereupon 

 he climbed uj:) and found the nest. 



The Hen-Harrier [Circus cyaneus). — Hill, the keeper of the 

 shooting about here, tells me that he often sees a strange hawk, 

 but that it is too wary for him to shoot it. From his description, 

 " blue on the back," " with white feathers above the tail," the bird 

 seems pretty clearly referable to the hen-harrier ( Circus cyaneus). 

 It may be, of course, although less probably, Montagu's harrier 

 ( Circus cineraceus), but that could only be determined with the 

 bird in hand — not that I am at all desirous of doing so. The 

 presence of a few individuals of our rarer species of hawks might 

 well be encouraged, for by reason of their extreme scarcity they 

 could never appreciably interfere with the preservation of game, 

 and a little protection afforded them would not seriously conflict 



