Begun. — On the Habits of Prionoplns reticularis. 285 



any kind of substantial nourishment, and, thouglx inactive, is in reality 

 undergoing important changes. Now, for the first time, may be seen the 

 result of those marvellous transformations which have occurred since the 

 female laid the egg, as the form and structure of the imago, or perfect insect, 

 can clearly be traced. 



The beetle issues from the pupa stage during autumn or spring, in the 

 former case generally remaining quiescent during the winter, and, in the 

 vast majority of cases, is short-hved, appearing, indeed, to exist no longer 

 than is necessary for the propagation of the species. It is evident, there- 

 fore, that the imago does comparatively little injury, whilst many of the 

 predaceous ground-beetles, which frequently live throughout the spring and 

 summer, destroy vast numbers of insect pests. We are indebted to the 

 microscope and the investigations of many learned naturalists for our 

 knowledge of the anatomy of Coleoptera, the details of which, however, 

 scarcely come within the scope of this paper. Suffice it to say, that the 

 internal organs consist of a stomach, pouch, gizzard and gullet, for the 

 assimilation of food, several " hearts " united by what may be called veins 

 for the circulation of the blood, and the air-tubes previously alluded to 

 under the heading "larva." The anatomical structure can only be advan- 

 tageously studied in works specially devoted to that branch of the science ; 

 the external form, infinite in variety, may, so far as the indigenous Coleop- 

 tera are concerned, be studied in the volume now being published by the 

 Colonial Government.* Many people are under the impression that a beetle 

 "grows" considerably; that, however, is a mistake, as the ultimate size of 

 the insect is determined in the larval state, the development depending on 

 the quantity and suitabihty of the nutriment available. 



The foregoing remarks having, I hope, served their purpose, id est, 

 enabled those, whose vocations have not permitted them to become entomo- 

 logical students, to realize in their own minds something approaching an 

 accurate conception of the nature of the forms recognized as Coleoptera, 

 I now subjoin descriptions of the larva and pupa of Prionoplus reticularis, 

 our largest longicorn beetle. 



Larva cream-coloured, sub-cylindrical, attenuated posteriorly, twenty-one lines in 

 length, composed of thirteen very distinct segments, of which the first forms the head ; 

 the second is the broadest, measuring 6J lines across ; the next four are the shortest, and 

 about equal in breadth to the second ; the others gradually increase in length, and the 

 eleventh is rather broader than the immediately preceding ones. The head is more or 

 less infuscate, the parts of the mouth being pitchy-brown, and is seemingly capable of 

 being retracted within the second segment ; it is rounded and densely ciliated in front, 

 the line of demarcation between its anterior and back parts is obvious, the depressed 

 front angles of the latter portion are formed, just behind the lower part of the base of 

 the mandibles, by distinct tubercles ; there are four other, but much smaller, elevations 



* Coleoptera of New Zealand, by Capt T. Broun. 



