3 22 First Report on Economic Zoology. 
more or less soft, not a hard, rigid shell. The egg gives rise to the 
■so-called larval stage, which resembles the adult, except that it has 
six instead of eight legs, and they are usually colourless and semi- 
transparent. This larval stage does not last long, a single ecdysis 
bringing it to the third or nymph condition. 
The nymph resembles the adult when nearing maturity, but when 
young it has the appearance of the larva. This is the period when 
the mite grows, and it assumes its fourth pair of legs. The nymph 
casts its skin twice. Another curious stage exists in these acari, 
namely, the hypopial stage, in which the mite assumes a different 
appearance — a stage in which it can more easily be distributed from 
place to place by becoming attached to flying insects, etc., but in the 
two furniture pests this stage is rudimentary ; in G. domesticus it 
never emerges from the young nymphal skin, and in G. spinrpes it 
seldom does so. This “ skin-like ” case protects the mite and so 
enables it to withstand heat, moisture, etc., and in this stage it may 
very easily be distributed from place to place by the wind. The 
wind may also spread these minute creatures in other stages as well. 
The “ feather-bristle ” mites, or Glyciphagi , may often be noticed 
in houses suffering from dry rot. They do not seem to do any 
material damage in a house except to stored goods, unless it is by 
carrying the spores of dry rot fungus about. Mr. White stated in 
one of his communications, a the white insects give considerable 
trouble on my furniture ; perfectly harmless, but unpleasant.” They 
may also be noticed in abundance in furniture attacked by the furni- 
ture pest — the Death Watch ( Anobium iessallatum ) — living amongst 
the dust and debris these pests produce. 
Treatment. 
Washing well all likely corners where they may shelter with a 
.strong solution of “ Chinosol ” was recommended. Failing this, 
fumigation with hydrocyanic acid gas or disulphide of carbon might 
be tried. These, of course, are poisonous, also the fumes, and bisul- 
phide of carbon is also inflammable, so must be used with care 
{vide p. 126). 
A further letter regarding fumigation for this pest was received 
from Mr. Howard White, to which the following answer was sent : — 
Your letter has not been answered because I was waiting the result 
of some experiments Prof. Hall was making for me re bisulphide of 
carbon. He finds it will not hurt gold picture frames, etc., unless there 
are impurities in the gold. Nor will it hurt furniture, foods or draperies 
