284 Transactions. — Zoology. 



Aet. XXXV. — On the Habits of Priouoplus reticularis, idth Diagnoses of the 

 Larva and Pupa. By Captain T. Begun. 

 [Read before the Auckland Institute, 2nd June, 1879.] 

 The subject I propose dealing with will be rendered more intelligible, and 

 perhaps interesting, if I endeavour to convey something like a clear idea of 

 what is meant by the terms employed by naturalists to designate the meta- 

 morphoses of insects. This course will seem all the more advisable when it 

 becomes known that I possess specimens of the larvae and pupae of other 

 species of Coleoptera, which I hope to describe in subsequent papers. 



A beetle originates from a minute, soft, oblong or oval egg instinctively 

 deposited by the parent in such a situation as will ensure a sufficient supply 

 of wholesome food, the mode, time, and place of deposition being liable to 

 considerable variation, and ordinarily succeeded by the death of the female, 

 whose chief purpose in life would thus appear to have been accomphshed. 



From the egg, in course of time — varying in extent according to species, 

 climate, or other cu'cumstances — emerges the larva, which fi-equently passes 

 a period of three, or even five years, in solid wood before it attains its full 

 growth and becomes a pujoa. It is chiefly during this stage of an insect's 

 existence, according to the mode of life of the members of the group or 

 genus to which it belongs, that it commits so much havoc, or proves of 

 great service to man. The larva — the state analogous to that of the cater- 

 pillar of the butterfly or moth, and the maggot of the common fly — is usually 

 a fleshy grub composed of thirteen segments, of which the first forms the 

 head, the next three the thorax, and the remaining nine the abdomen of 

 the perfect beetle ; but two or more of these latter ultimately coalesce in 

 such a manner that not more than five or six can be discovered in many 

 Coleoptera. It is provided with six short legs, which are attached to the 

 second, third, and fourth, or thoracic segments. The head is furnished 

 with a pair of rudimentary eyes ; two antenna, commonly called feelers, 

 situated between or near the mouth or eyes ; two pairs of transverse or 

 horizontally-moving jaws, of which the upper are termed mandibles and the 

 lower maxillte, the latter ordinarily armed with feelers, called palpi ; a 

 labrum or upper lip ; and a labium or lower lip, having a pair of palpi. 

 These organs, conjointly, close the aperture of the mouth when in repose. 

 Kespiration is effected, not through the mouth, but by means of a variable 

 number of small, often almost imperceptible orifices referred to in descrip- 

 tions as spiracles or stigma ; these are placed near the sides of the body, 

 and communicate with internal air-tubes. 



In due time the larva assumes the form known to us as the pupa, which 

 corresponds with that of the chrysalis of Lepidopterous insects. In this state 

 th<9 beetle is generally soft, and quite harmless — that is, it does not take 



