THE NOCTUINA. 
25 
not noticed in any other of the Lepidoptera , and their use is 
by no means evident. When ready to assume the chrysalis 
state the lobster caterpillar spins a slight cocoon, and protects 
it with leaves. 
The largest group of the order of the Lepidoptera is called 
Noctuina. The majority of night-flying moths belong to it, 
and they are very properly named after their nocturnal habits. 
As there is no rule, even in Nature, without an exception, so 
we find that several kinds of the Noctuina fly by day, and 
enjoy the sunlight as much as any butterfly. The number of 
species in this group is immense, and about 800 are pretty well 
known in Europe, and there are about 300 British species. 
Naturalists meet with great difficulties in classifying them 
into genera, and even their specific differences are either very 
hard or impossible to make out. There are no satisfactory 
distinctions between some of the moths which enable any one to 
say that they are of such and such species, and very frequently 
they are separated into different kinds, because they happen 
to feed upon various plants, and because the moths are not all 
coloured in the same manner. Of course the entomologists 
that believe in the real nature of species have taken a vast 
deal of trouble with the Noctuina , but those who do not think 
a species to be anything more than an abstract idea, and that 
it really consists of the sum of the variations of a closely 
allied series of forms, do not see the use of this natural 
history hair-splitting. The comparative study of a sub-group of 
the Noctuina is certainly very instructive. There are ten, 
twenty, thirty, and more kinds of moths whose structures are 
in the main alike, there being only the appreciable differences 
produced by the details of their ornamentation. Their dis- 
tinctive characters are so feeble that no philosophical naturalist 
would care to call any of the species other than varieties of 
some common type. In fact, in studying these Noctuina in 
the adult form, every one must admit that they oppose the 
notion of species in its ordinary acceptation. The most inte- 
resting part of the examination refers to the caterpillars, for 
those belonging to moths, which are almost exactly alike, 
present very marked distinctions. The moths resemble each 
