21 
only noteworthy for their great powers of flight, but also for the very 
strange habit, “sembling,” that is, the collecting together of large 
numbers of the males, drawn from long distances by the females, 
| examples of which had been detailed to the Society on former 
occasions. 
: Among these Lifaride were those pests to the orchards 
4 of Kent, the brown-tail and gold-tail moths. The caterpillars of alj 
were hairy, some were characterized by peculiar tufts of hair, as seen 
in the well-known hop-dog, while the common vapourer (Orgyia 
antigua), and the scarce vapourer (Orgyia gonostigma) had tufts of 
long hair as well, pointing over the head like brushes, each hair 
being tipped with a small knob. The caterpillars of the first (Orgyia 
antigua) fed on many plants and shrubs, while the latter fed on the 
nut and oak, and each, when it was about to change to the chrysalis, 
_ spun a loose web intermingled with its hairs, and turned into a hairy 
chrysalis. The moths, which escaped from the chrysalides, were, 
from their peculiar rising and falling flight, called “ vapourers.” The 
males of both species had slender bodies and very broad wings, and 
were met with, not simply in the country, but in the very heart of 
towns and cities. At the proper time of year they might be seen 
“ vapouring” among the trees on the Level. 
The females of both species were nearly wingless, had large bodies, 
and were as unlike moths in appearance as was possible to conceive. 
The colour, too, differed from that of the active males, being of a dull 
grey or ashy brown, while the males were richly tinted, and in one 
case marked with a white spot on the upper wing. So slight was the 
_ power of locomotion in the female, that she very seldom got beyond 
_ the empty cocoon on which she laid her eggs and died. But though 
_ s0 unattractive to human eyes, they were not to their male admirers, 
4 as might be proved by taking a newly-escaped female into the neigh- 
 bourhood of male vapourers, for then they came flitting around, and 
_ soon settled on the box containing the captive female. 
The next examples would be taken from a very large family of 
moths, the caterpillars of which differed from those of other moths and 
_ butterflies in the number of their “ false legs,” and also in their mode 
of progress. ‘The caterpillars of moths and butterflies possessed, as 
_ was generally known, six truc legs, and in addition ten false legs or 
_ “claspers,” by means of which they held on. In one great family 
most possessed only four of these claspers, which were situated at the 
_ tail end, so that the caterpillar could not hold on by the middle of the 
“body ; the consequence was that when it walked the middle of the body 
