Vlil PREFACE. 



whether, amongst the British kinds, there are many, or any, whose 

 larvae are entirely immune from such attacks ; and, if any, were they 

 conspicuous larvae?^ We now know many species of the former 

 genus to be freely preyed upon, though I once bred over a score of 

 C. verbasci, taken at large in the full-fed larval state, without a trace 

 of parasitism ; and I have also found that of Diloba caenileocephala 

 bearing agglutinised Apanteles cocoons. Tugwell states- that he at one 

 time had two hundred larvae of Deilephila gnlii, not one example of 

 which showed the least sign of a parasite. Nevertheless, the appended 

 list of hosts will indicate that, at least at present, we cannot pronounce 

 with anything approaching positiveness upon the question, the solution 

 of which requires so much especial investigation. 



The central European zone — that lying between the 42nd and 54th 

 degrees of latitude"' — is said to be the most prolific of these insects which 

 appear to affect a temperate climate, since in the tropics, where they attain 

 large proportions and brilliant coloration, their numbers appear to be 

 proportionately vastly inferior. This, however, may to a great extent be 

 due to the fact that Sweden, Germany, Belgium and France are the most 

 thoroughly worked countries; very little is known in this respect regard- 

 ing Russia, or the eastern and southern parts of Europe ; and Berthoumieu 

 is of opinion that when these districts are adequately explored the number 

 of European species of Ichneumoninae will be doubled. As regards our 

 present knowledge of the number of the above sub-family alone, about 

 800 have been described, of which some 310 are herein brought forward 

 as pertaining to Britain. Rev. T. A. Marshall informs me * that he con- 

 siders the species of the world's Ichneumonidae to reach the vast total of 

 some 710,000. 



Considering our ignorance of these insects, a quite surprisingly large 

 number of local catalogues of British species have been published, 

 comprising lists from Alderne}', Barnby Broad in Suffolk, Dorsetshire, 

 Devonshire, South Devon, Glanvilles Wootton, Great Yarmouth, Hastings 

 District, Isle of Man, Land's End, New Forest, Norfolk, South-west 

 Ireland and Yorkshire, which will be found under the "Works Consulted." 

 Many of these records, however, from a variety of more or less obvious 

 reasons, must be accepted aim g?-ano salis, and, where verification has 

 been impracticable, they are here recapitulated for whatever they may 

 be worth. Such as they are, these lists go to show that the distribution, 



1 Proc. Ent. Soc, 1867, p. 81. 



2 Young Naturalist, 1890, p. 94. 



8 Land's End is 50 degrees, Newcastle 54 degrees. 

 i Marsh., in lit., 2nd May, 1902. 



