REPORT ON THE LICHENS OF EPPING FOREST. 
97 
dwelling lichens,like cattle in a meadow. Michael, in his British 
Orihatidce 1883, describes numerous species of these mites as 
haunting, and feeding upon, Lichens and specially mentions 
four species as being “ true lichen-loving creatures, seldom 
found elsewhere.” one species indeed ( Orihata parmelice) owes 
its specific name to its lichen-habitat. Of the nymph of this 
form ( 0 . parmelice), Michael notes that its bright-orange-yellow 
colour resembles that of the lichen upon which it feeds ( Physcia, 
or, as it was formerly called, Parmelia , parietina) and suggests 
that this may be a case of protective resemblance. 
We have noticed other scarlet-and-black, oval mites (ap¬ 
parently not of this family), with whose names we are not 
acquainted, crawling in numbers over the thalli of lichens on 
tombstones at Loughton and Theydon Bois, but whether ac¬ 
tually feeding upon the plants could not be decided. Specimens 
of Parmelia have frequently been seen by us with the thin green 
cortical layer wholly or partially eaten away, possibly by mites, 
leaving the white woolly medullary layer exposed. 
Some Podurae, also, frequent lichens growing on walls. 
Many moth-caterpillars feed on lichens on trees and walls ; 
nearly all the “ Footmen ” moths ( Lithosiidce ) do so,for example ; 
and we have several striking instances, both in the case of the 
larva and of the perfect moth, of protective coloration and 
resemblance to the lichens upon which the insects rest. A 
very striking example is Moma orion, a common moth in many 
parts of Europe, though rare in this country ; specimens of the 
imago of which, at rest upon the lichen-covered bark which 
they frequent, are exhibited at the Natural History Museum 
at South Kensington ; other quite common British moths, as 
Bryophila muralis, B. perla and Agriop sis aprilina, are 
examples of this resemblance, and the ground tone of the colora¬ 
tion of the wings of these moths is stated to vary according 
to the prevailing hue of the lichens which they select for their 
resting place. 
One of the most remarkable examples of this protective 
resemblance to lichens is that of the larva of the geometrid 
moth ,Cleora lichenaria, which feeds upon foliose lichens growing 
upon tree-trunks and palings, and being of a green-grey hue 
and possessed of two little humps on many of their body-seg¬ 
ments, they so exactly resemble the lichens in colour and appear- 
