Pupa is named from its resemblance to a chrysalis, the apex being rounded.
Pupa incompletely obtect or free, and enclosed in the hardened cuticle of the last larval instar (puparium).
After the second larval moult, he passes through a passive stage comparable to the pupa-stadium of an b insect, and during this stage, which occurs inside the root, the reproductive organs are perfected.
The wing, when not in use, is folded d Pupa of Dyticus.
The majority of authors, however, follow Brauer in dividing the order into two sections, Orthorrhapha and Cyclorrhapha, according to the manner in which the pupa-case splits to admit of the escape of the perfect insect.
In the Orthorrhapha, in the pupae of which the appendages of the perfect insect are usually visible, the pupa-case generally splits in a straight line down the back near the cephalic end; in front of this longitudinal cleft there may be a small transverse one, the two together forming a T-shaped fissure.
- e,f, Owl moth (Heliothis armigera); a,b, egg, highly magnified; c, larva or caterpillar; d, pupa in earthen cell.
Amongst insects with imperfect metamorphosis the nearest approximations to the true pupa of the Holometabola are to be found in the subimago a From Chittenden, Bull.
- a, Saw-toothed Grain-Beetle (Silvanus surinamensis); b, pupa; c, larva, magnified 12 times; d, feeler of larva.
Only a brief reference can be made here to the fascinating subject of the life-relations of the larva, nymph and pupa, as compared with those of the imago.
With the appendages not fixed to the body, as is the case in the pupa of most moths.
In the Cyclorrhapha on the other hand, in which the actual pupa is concealed within the hardened larval skin, the imago escapes through a circular orifice formed by pushing off or through the head end of the puparium.
A gnat pupa swims through the water by powerful strokes of its abdomen, while the caddis-fly pupa, in preparation for its final ecdysis, bites its way out of its subaqueous protective case and rises through the water, so that the fly may emerge into the air.
But the pupa hangs from the surface by means of paired respiratory trumpets on the prothorax, the dorsal thoracic surface, where the cuticle splits to allow the emergence of the fly, being thus directed towards the upper air.
Mandibles present in pupa, vestigial in imago; maxillae suctorial without specialization; first maxillae with lacinia, galea and palp. Prothorax small.
The standing of the Trichoptera in a position almost ancestral to the Lepidoptera is one of the assured results of recent morphological study, the mobile mandibulate pupa and the imperfectly suctorial maxillae of the Trichoptera reappearing in the lowest families of the Lepidoptera.
These gradually become larger, and when so the creature may be said to have entered its "nymph" stage; but there is no condition analogous to the pupa-stage of insects with complete metamorphoses.
G, D, Pupa of Culex.
- a, Pear Saw-fly (Eriocampoides limacina); b, larva without, and c, with its slimy protective coat; e, cocoon; f, larva before pupation; g, pupa, magnified 4 times; d, leaves with larvae, natural size.
- Passive Nymph or " Pupa " of male scale-insect (Icerya).
He even noted the fact that the pupa of the flea is sometimes attacked and fed upon by a mite - an observation which suggested the well.
When the larva is fully mature, and ready to change into the pupa condition, it proceeds to spin its cocoon, in which operation it ejects from both glands simultaneously a continuous and reelable thread of 800 FIG.
It is important to note that the scales are present when the moths first emerge from the pupa-case, but are loosely attached and fall off with the first flight.
It hides itself in the ground during the winter, and in the spring it passes into the pupa stage, from which it emerges about August as the full-grown insect.
- A, Wireworm; B, pupa of Click Beetle; C, adult Click Beetle (Agriotes lineatum).
Weismann (1863-1864) traced details of the growth of embryo and of pupa among the Diptera, and A.
After many years the larva is transformed into the pupa or nymph, which is distinguishable principally by the shortness of its antennae and the presence of wing pads.