=~ 
and after a time the skin splits, and is shed with greater 
less wriggling, A sticky, varnish-looking moisture covers the 
different-looking thing which now presents itself, and dries 
rapidly, and forms a case over the skin of the ‘‘ pupa ” beneath. 
The alterations within and without the insect at this time, that is 
to say, during three or four days after leaving the cabbage, are 
rried out with great rapidity, and the future butterfly is well 
shadowed at this period in the structure of the chrysalis or 
ny Hanging as a chrysalis or pupa in a perfectly immobile 
ondition, neither seeing, hearing, nor tasting, and losing very 
little weight from the exhalation of its moisture, the insect lives 
on for many months, and until spring has nearly ended. Then 
the dark case splits, and a tender white butterfly crawls forth, 
and, under the influence of warmth and the sun, becomes dry, 
p 
é 
Ci 
‘Fic. 2.—CEisophageal Epithelium. 
stretches, and unfolds its crumpled-up wings, walks feebly upon 
long legs, trails a short body, moves a curious flexible trunk in 
front of its head, the result of the modification of its former jaws, 
and takes to flight. The common white butterfly, whose solitary 
_ flight is so zigzag and wandering, and whose flight in company is 
so tumultuous, ascending and vibrating, lives for love, It has a 
_ soul above cabbages, and rarely condescends even to sip or suck 
_ the daintiest nectar from flowers. After a longer or shorter ex- 
_ istence, it begins to lay eggs, and places them in the immediate 
Fic 3.—Stomach Structure. 
neighbourhood of the favourite food of the larva, which are 
to come from them. 
Another familiar example of perfect metamorphosis may be 
studied in the instance of oneof the false wasps, Odynerus parielum. 
_ This small wasp-like insect may be seen on the other side of the 
Channel in great companies on lucern and clover when in full 
flower. It is a solitary kind, and the male and female care 
‘nothing for their companions, who rush and tumble over, in, 
and about the flowers, sucking their sweetness, and squabbling 
2 
Fic. 4.—Pylorus. 
and flying for the freshest corollas. Day after day this buzzing 
busy crowd may be seen leading a life of happy enjoyment, feed- 
ing, playing, and flirting ; but after a while an unusual excite- 
ment is noticed amongst a large number of the insects. These 
extend their flight beyond the favourite field, and seek the neigh- 
bourhood of sandy clayey banks close by. They may be ob- 
served digging their heads into the sand with great assiduity, and 
pulling out sand grains, and gradually forming a hole, Each 
wasp works independently of its neighbour. As soon as the hole 
| out from the bank and opens into the tunnel. 
> 
31 
is large enough to admit the wasp’s body, the legs remove, by a 
process of brushing, the particles loosened by the jaws. After a 
short time the wasp will be found to have made a tunnel, and the 
constant out-pour of sand and clay indicates that excavation is. 
still proceeding out of sight. 
Soon the Odynerus perfects two or three chambers deep 
in the bank and opening into the tunnel. She (for it is 
the female who does the work) carefully pounds the insides 
of the cavities and removes all roughness from them, and leaves 
them as commodious hollows, water-tight, and not likely 
to fallin. This is not all. On coming back into the light, the 
wasp seizes cylindrical pieces of earth, and moulds them more or 
less into shape with her jaws, and places them in front of each 
other, and side by side, so as to form a hollow tube, which sticks 
The free end of 
this ante-chamber is left open, and the pieces of which the whole 
is formed are gummed together and pressed. The tube is ex- 
Fic. 5.—Stomach Structure of Pupa. 
tremely fragile, and the pieces of it are not in contact everywhere, 
Nevertheless, the Odynerus passes along it readily enough, but 
no other insect of its size can do so. All this work is carried on 
whilst the wasp appears to be in an intense state of excitement, 
and when it is completed the insect flies off to the flowers again, 
But not to return to its former habits. On the contrary, the 
purposeless tumbling about of flowers, and the occasional sip of 
nectar, are forgotten, and the flighty little vegetarian becomes a 
ferocious and ardent huntress of prey. She seeks the small larvze 
of a species of weevil which abounds about the plants, and seizing 
one, digs her sting into it, so that a weak venom is introduced 
close to the nervous system of the victim. The larva is paralysed 
Fic. 6.—Stomach Structure of Imago. 
at once, but not killed ; on the contrary, it remains motionless, 
but lives. She then flies off with her prey to the bank, enters 
the tubular ante-chamber, traverses the tunnel, and reaches one 
of the chambers. Here she deposits her insensible victim, and 
lays one egg close to it. Returning again to the field, she seizes 
another larva, stings it, and carries it off to deposit it close to the 
first. This procedure is repeated as many as thirty times, and 
the chamber becomes full of insensible weevil larve and one 
Odynerus egg. The other chambers are filled in the same man- 
ner, and an egg is laid in each. Then the wasp comes out of the 
tunnel for the last time, breaks down the tubular ante-chamber, 
so as to hide the entrance to the tunnel and chambers, flies off, 
and dies. She never sees her offspring, for which she, a vege- 
tarian, has provided animal food in abundance, , 
