62 THE ENTOMOLOGIST S RECORD. 
M. affinis, M. subflavella, and F’. casta vary from -200mm. to 
-203mm. (except one I’. casta :210mm.), I. intermediella -216mm.- 
-297mm., I. bowerella -240mm., I’. germanica:182mm.-"194mm. The 
numbers are no doubt too small to found any strong conclusions upon. 
In some degree these differences may be of value as specific characters, 
as, for instance, in the case of F’. bowerella ; but even in this instance 
we find the rule holds that pectinations are of uniform length through- 
out the genus, but that the length of antennal joints varies directly 
with the size of the insect and inversely as the number of joints. 
Great reliance has been placed for distinguishing species on the 
form, size, and colour of the wings. Perhaps I unduly depreciate 
these, my first impressions having been formed by attempting to verify 
some distinct characters of this sort between the I’. roboricolella, F’. 
nitidella, F’. intermediella, and M. crassiorella of our British collections, 
working all the time as I now believe entirely within the limits of one 
species. Apart from this, however, these characters are not very 
valuable. As to colour, with the exception of the reticulate species, 
and perchance of M. subflavellaand M. edwardsella (saxicolella ?), all the 
species can be very black when fresh, but vary a good deal, and all 
become a snuffy brown with age (especially if assisted by a little 
damp). The form of the wing varies within the limits of a species to 
some extent, and is very difficult to define as between different species. 
In our English series unquestionably the apparent form of the wing is 
much more dominated by various styles of setting than by any inherent 
character. All the species have a certain amount of natural curvature 
of the wings and of pleating or folding at the nervures, and the extent 
to which these are straightened out by pressure and flat setting, or 
exaggerated or altered by drooping or bad setting, much outweighs any 
actual difference of form in the appearance of the insects. 
(To be continued.) 
British Dragonflies*. 
By MALCOLM BURR, F.Z.S., F.E.S. 
Tt is with a real pleasure that we weleome Mr. Lucas’ handsome 
work on the dragonflies of Great Britain (and we observe the Channel 
Islands are included), for, apart from the interest that the book evokes 
by its own merit, it supplies a badly felt want in the literature of the 
zoology of the British Islands. Hitherto the collector of dragonflies 
has had to be satisfied with Harcourt-Bath’s brief account, unless he 
were able to consult the various periodicals dealing with the subject 
in various languages, or Mchachlan’s purely scientific work. It 
is this lack of a complete popular account of our Odonata that has 
doubtless frightened many a beginner from the study of so interesting 
& group. 
In the introduction, the author cites the latest census, quoting 
W. F. Kirby’s work of 1890, which enumerates 1800 species of known 
recent Odonata, and suggests that, by future investigation, four times 
this number might be discovered. Of these 1800 species, 39 are 
British. There are further seven reputed species, always an irritating 
*« British Dragonflies (Odonata).” By W. J. Lucas, B.A., F.E.S. [Upcott 
Gill, 1900, 8vo., pp. 1-856. With 27 coloured plates, and 57 figures in the text. 
Price 31s. 6d.] 
