XV THOMISIDAE A13 
are much smaller and darker. It is common in some parts of 
England, especially in the south, where it is to be sought for in 
bushes and trees. 
Diaea dorsata is one of our prettiest British species, with hght 
green legs and cephalothorax, 
and a yellow abdomen with a 
red-brown central marking. 
It is common in the New 
Forest and other southern 
localities. The female attains 
a quarter of an inch in 
length. 
Thomisus onustus, a rare 
spider among heather, is recog- 
nisable by the shape of its 
abdomen, which 1is_ broadest 
behind and abruptly truncated. 
When adult the abdomen is a 
pale yellow, but the young are 
suffused with a pink hue closely 
corresponding with that of the 
heather blossom in which they 
are frequently found sitting. 
Gi.) The PHILODROMINAE 
have the cephalothorax more 
rounded in front, and the 
legs, especially the second pair, Fra. 213.—Thomisid spiders. A, Micrommata 
usually longer than in the virescens, 9; B, Xysticus pini, 9; C, 
Morais! Un aracrdreten pee margaritatus, 6; D, Tibellus 
oblongus, 2 . 
genera, of which the most 
important is Philodromus, which numbers about a hundred species. 
They are active spiders, living upon bushes and trees, and most 
of them are inhabitants of temperate regions. We have about 
twelve species in the British Isles. The commonest is Ph. awreolus, 
which is abundant on bushes in most parts of the country. 
Some species are very prettily marked, and one, Ph. margaritatus 
(Fig. 213, C) presents a very good example of protective colora- 
tion, being almost indistinguishable on the blue-grey lichen on 
tree trunks, where it lies in wait for insects. 
Another important genus, including some fifty species, is 
