no 



On the Entomology of the 



[July 



I have made, worthy of still further investigation, that most of the In- 

 sects which are identical in both countries, are either coprophagous or 

 phjtyphagous ; in short, vegetable feeders, which circumstance would 

 lead one to suppose a similarity of vegetation in the different regions. 



It may here be expected, perhaps, that I should state the relative pro- 

 portions of tlie carnivorous and phytyvorous Insects ; and I cannot but 

 regret that I have not ap yet followed up my investigations sufficiently to 

 enable me to draw a satisfactory conclusion. Messrs. Kirby and Spence, 

 in their interesting work, speaking of our British Fauna, esteem these 

 groups as nearly equal in number. I must confess my own observation 

 induces me to believe, tliat the latter greatly exceed the former in our 

 own country. With respect to the phytyvorous group in tropical climates, 

 they certainly greatly out-number the carnivorous; and were it not so, 

 the air in those regions would scarcely be habitable, considering the nau- 

 seating effluvia arising from excrementous matter, which the Copridas in 

 particular tend to neutralise, by consuming, decomposing, and burying in 

 the earth, all that is obnoxious and liable to putrify. In proof of this 

 assertion, I will only here add, that five of the greatest groups with 

 which we are acquainted, namely, the Lamellicornes, the Sternoxes, and 

 the Longicornes, the Curculionidse and Chrysomelidse, are almost entirely 

 phytyvorous or xylobious ; and it may also be naturally inferred from the 

 superabundance of animal Hfe of all classes within the tropics, particu- 

 larly the Ruminantia, that there also vegetation will be found most luxu- 

 riant ; yet, looking to Insects only, we find they are scarcely sufficient to 

 keep in check its excessive exuberance. In addition to multiplied forms 

 of genera, we have an extraordinary increase of species and of indivi luals. 

 It is in these same prolific regions also, that the mighty Goliuthi and gi- 

 gantic Prionidae abound, where they perforate the trunks of the proudest 

 monarchs of the forest, and hasten them onward to decay ; and, by means 

 apparently inefficient, check vegetation. It is time, however, to add a 

 remark on the carnivorous Insects, which, although inferior in numbers 

 to the phytyvorous, are still an important group ; and in northern regions, 

 by removing the decomposing matter from the decaying and putrifying 

 carcass, fulfil the functions assigned to them by Providence. In tropical 

 regions they are certainly not always so abundant, as a dead body, from 

 the natural dryness of the air, and intense heat of the sun, is frequently 

 dried up before putridity has made much progress ; at least, such is the 

 case in the Pampas. I cannot help thinking, however, although our ca- 

 binets contain but few species from equinoctial and tropical latitudes, 

 that eventually they will be found more numerous, and that in these re- 

 gions we shall still find them more proportioned to the excess of animal 



