w 
52 JIU. J. n. GURNEY ON ORNITHOLOGICAL MIGRATIONS. 
never seen Wasps in this position except -when hybernating. AVasps 
are subject to the attacks of several insects. One small Ichneumon 
{SjyJiecophaga vesparum) is produced from larvre which feed on the 
living AVasp grub. Chrysis, the lovely ruby-tailed fly, also is reared 
at the expense of the grubs. So also are several flies ; and besides 
these at least, one Beetle and one Moth live in AA^asps’ nests. 
There are seven species of Social AVasps natives of Great Britain, 
and of these six are found in Norfolk, — this number includes the 
Hornet, — and all are fairly common except one. 
AMI. 
A COMPAPJSON OF ORNITHOLOGICAL MIGRATIONS 
IN ENGLAND AND HELIGOLAND. 
By J. H. Gurney, Jun., F.Z.S. 
Read 2^th February^ 1885. 
Of all subjects connected with Ornithology, there is none so 
interesting, and none so difficult to comprehend, as Migration. 
The periodical return and departure of a vast number of Birds to 
and from their breed ing-(]^uarters has long been marked by a host of 
field naturalists. If all Avhich has been written upon it were 
collected, the volume would be huge indeed. Inferences have 
been drawn, comments have been made, and a good deal has been 
learnt about it ! but the matter still remains a wide field for 
speculation in many ways, though our knowledge is far in advance 
of what Selby, Montagu, Gilbert AVhite, and the continental 
naturalists of their time possessed. 
^Migration is a subject, the antirputy of which is immense. It 
was familiar to the Prophet Jeremiah, who enumerates four species, 
the Stork, the Crane, the Swallow, and the Turtle Dove, which 
kneiv and observed the time of their coming. It is almost as old 
