182 MR. NEWPORT ON THE NATURAL HISTORY, ANATOMY, 
and has ceased to feed, as at the period at which I have found the full-grown JMeloé, the 
muscles effect a complete alteration in the segments both relatively and individually. The 
abdominal segments, which are the largest while the larva is feeding, are quickly reduced 
in size when fresh nourishment has ceased to be supplied; while those of the thorax are 
enlarged, and duplicatures of tegument are formed between each by the shortening of the* 
longitudinal and diagonal muscles. 
In the pseudo-larva of Meloe (fig. 13) these changes have only commenced ; but when the 
insect passes to the nymph or pupa state (fig. 15), the alteration is carried to a very great 
extent. The longitudinal muscles of the abdominal segments occasion, by their powerful 
contraction, broad reduplications of the tegument, the posterior margin of one segment is 
made to cover the anterior of the one next behind it, and the whole are much shortened. 
The force of development in this region is from behind forwards, the effect of which is to 
occasion a rapid enlargement of the head and of the thoracic segments, and the coalescence 
of some of the latter by aggregation and anchylosis. This is carried to the greatest extent 
in the segments of the middle of the body, which form the union of the thorax and abdomen 
in the imago. In some insects the fifth segment of the larva is reduced to its minimum, 
and disappears as a sectional portion of the animal, its rudiments only being left. In the 
nymph or pupa of Meloe the metathoracic or fourth segment is the shortest, the fifth being 
further shortened at the next change. 
The immediate result of the altered proportions of the abdominal segments, and their 
removal forwards by the action of the muscles on the tegument, is a re-induction of the 
forces of growth in the appendages of the thoracic and cephalic segments, and a conse- 
quent enlargement of the segments themselves, more especially those of the head. This 
region in Meloe is enormously enlarged, as compared with the head of the larva. But 
this does not result, as M. Ratzeburg seems to think, from certain observations he has 
made on Hymenoptera, from a coalescence of the head of the larva with the segment next 
behind it, but it is entirely due to the rapid growth and expansion of all parts of the head 
at the period of transformation. 
The change effected while the larva is passing to the pseudo-larva state, is a com- 
mencement of a re-induction of the growth of the appendages of the head and thorax. 
The legs, then reduced to tubercles, are soon redeveloped beneath the tegument of the 
pseudo-larva in an entirely new form, with jointed tarsi, ready to be elongated at the 
instant of change to the nymph. 
In addition’ to the redevelopment of these parts, the rudiments of new organs are pro- 
duced. The internal respiratory structures are extensively affected by the changes, as is 
the case in all insects on becoming pup:e, and the result is to occasion the expansion of a 
idem add, Tho Vic some rin 
the future rudimentary UR the fune, ge mere. is Soon arrested, and it becomes 
N andit a qi e ; — other insects it is the anterior wing. 
ntu À , ORAY 1O menuon here, not only occasion these parts to 
j eloped to a greater extent in Some species than in others, but als ff a 
tion of a second fold from the o op e eee iu 
metathorax, the posterior wing. 
Besides these there are other important changes in the tegument in these transforma- 
