DISTRIBUTION BY ENVIRONMENTS 

107

examples of species which cannot be associated in our minds with any 

particular plants, so many do they favour. 

Others appear to have marked preferences and to flourish on 

relatively few. Though found, perhaps, on a number of plants these 

spiders may be regarded as having their headquarters on one or two. 

Just a few examples include 

Diaea dorsata 

Fab. (Yew, Box, Oak), 

Philodromus histrio 

Latr. (Heather, Gorse), 

Ballus depressus 

Walck. 

(Oak), 

Sitticus floricola 

Walck. (Cotton Grass), 

Theridion notatum

,

Linn. (Holly, Gorse), 

Drapetisea socialis 

Sund. (Beech, Pine), and 

Mangora acalypha 

Walck. (Heather). 

Competition between spiders is lessened by the selection of 

different parts of the plant on which to live and catch their prey. 

Different species are more or less restricted to the bole of trees, the 

roots of herbage, the trunks of trees, crevices in the bark, the stems of 

herbs, the branches or twigs, the leaves or flowers. 

Marpissa pomatia 

Walck., for instance, specializes on the heads of 

Phragmites

,

and 

Sitticus floricola 

Walck. on the fluffy heads of Cotton Grass. 

Aranea 

sexpunctata 

Linn. spends its days beneath the loose bark of trees, for 

which its flattened body suits it. The elongated bodies, colour, and 

stance of 

Tibellae 

and 

Tetragnathae 

suit them for life on the stems of 

herbs. The colour of 

Misumena 

and 

Thomisus 

for life in flowers. The 

colour and somewhat flat bodies of 

Drapetisca socialis 

Sund. and 

Philodromus levipes 

Linn. for life on tree trunks (and lichen on tree 

trunks in the case of the latter). Examples could be multiplied, but we 

should be trespassing on the subject of protective resemblance, with 

which we shall be dealing in our second volume. 

Specialization for life on a limited number of plants is indicated in 

some of these examples, but this is carried to its extreme in the case of 

a Malaysian spider, 

Misumenops nepenthicola 

Poc., which restricts 

itself to, and is adapted for, life within the pitchers of 

Nepenthes 

gracilis 

Korth.