4G8 



ENTOMOLOGY. 



< -in ii-il on, ;iiid thr place forms (In: cliicf retail mar- 

 ket for H largo surrounding district. Population 

 u! town in 1691, f7%; of parish of Enniskillen, 

 I 1.777. 



ENTOMOLOGY, (a.) The last twenty years 

 have done much for the science of Entomology, in 

 its nomenclature, in the addition of species of insects, 

 and in their systematic arrangement, and, more than 

 tliU combined, in rendering it a favourite and popu- 

 lar science, by the dispersion of prejudice and the 

 diffusion of a taste for the investigation of objects 

 so replete with all that can prove attractive. It 

 >eem.< hopeless to endeavour to arrive at any satis- 

 factory conclusion relative to the probable num- 

 ber of the species of insects spread over the earth. 

 Various calculations have been made, the discre- 

 pancies of which are perfectly ludicrous, if we 

 view them without reference to the circumstances 

 and data whence they were deduced. It appears 

 plausible to argue from the materials in hand, 

 namely, from any assiduously elaborated Fauna, 

 upon the relative numbers of the different orders ; 

 for some, the Coleoptera and Lepidoptera have 

 been very generally the favourites, and consequently 

 more carefully and universally collected than either 

 of the other orders ; but still the result will be far 

 from conclusive, for such a Fauna will necessarily 

 be of a country seated within the temperate zones; 

 and to conclude thence upon the relative numbers 

 of the orders within the tropical regions, and of 

 countries so differently circumstanced both in cli- 

 mate and geological structure, is merely to hazard 

 conjectures without the least hope of- even an ap- 

 proximation to the truth. The data whence they 

 must proceed are exceedingly incorrect; for the 

 number of the two orders which should form the 

 basis of the calculation have not, in those regions, 

 been yet so nearly ascertained as to enable us to 

 form a clear idea, the minute species having been 

 hitherto very much neglected. It has been gene- 

 rally supposed that small insects are rare within 

 the tropics and tropical climates, from their seldom 

 being sent to Europe. That the reverse of this is 

 closer to the truth, is clearly shown by a fact men- 

 tioned by Reich, who says that he commissioned two 

 friends, one residing at Rio Janeiro and the other 

 at Buenos Ayres, to collect all the minute Coleo- 

 ptera they could find, and that, in consequence, he 

 received from the latter place a four-ounce bottle 

 filled with spirits, which contained 1200 minute 

 insects, among which there were 116 new species 

 and from Rio a very small box, holding 216 impaled 

 beetles, comprising 102 species, almost all of which 

 were new and unknown and from the same local- 

 ity a half-ounce pill-box, which held 621 loose in- 

 sects, consisting of more than 100 new species as 

 small as any found in our more northern countries. 

 It must be remarked, that in both instances they 

 were collected at a very unpropitious time of the 

 year, in the course of a few days, within a limited 

 space, merely as specimens to ascertain if they were 

 what the European friend desired; whence it is 

 easy to conclude that they were not captured by 

 Entomologists, who would necessarily have been 

 aware of the interest attached to what they sent, 

 and consequently, as well as knowing better where 

 to seek, they would, in the same space and time, 

 have caught probably five times as many. We may 

 therefore consider, that minute species are as 

 abundant in proportion to the larger ones within 

 the tropics as they are in the colder regions; and 

 if go in the Coleoptera, why not in the Lepidop- 



tera, and then in their parasites, the pupivorous 

 iiymenoptera and the parasitical Hymenoptera in 

 general, which we know to be almost innumerable 

 in Europe and in our own country, from the hosts 

 already described by Gravenhorst, Nees, and our 

 two able and assiduous compatriots, Messrs Walker 

 and Halliday ? The Diptera also will necessarily 

 abound. Looking thence to the other orders, we 

 do not feel so much astonished at the calculation 

 made by Reich, who estimates the number of the 

 species of insects at possibly a million. This mul- 

 titude seems vast ; but compare it with the num- 

 ber of individuals of a single species frequently ob- 

 served ; the myriads of minute gnats occasionally 

 seen sporting over pools and under trees ; the in- 

 finite hosts of ephemera that by myriads of mil- 

 lions emerge, at a certain season of the year, from 

 some of the rivers of France, as described by 

 Reaumur ; the clouds of locusts, which even in- 

 tercept the rays of the sun, and devastate whole 

 provinces, and in the course of a few hours trans- 

 form a smiling and fertile country into a wild waste 

 and desert, threatening its whole population with 

 famine ; the innumerable plant-lice which desolate 

 our hop-grounds, and their enemies the lady-birds, 

 which have been taken up by pailfuls upon our 

 coasts, and have completely covered the ocean at 

 some distance from land ; and the number of the inha- 

 bitants found in the bee-hive, the ant-hill, and the 

 white ants' nest. If nature, in frequent instances, 

 has rendered species thus prolific in individuals for 

 peculiar purposes, can we rationally doubt her capa- 

 city of being equally fruitful in the production of 

 species, when we take into consideration the im- 

 portant variety of their functions, and the very 

 varied nature of soil and temperature, of heat com- 

 bined with humidity and dryness, and the dissimili- 

 tude of organization resulting from these diffe- 

 rences of combination ; and when we reflect that 

 in our own country every day almost adds to our 

 indigenous tribes, although they have been assidu- 

 ously collected for many years past, a million 

 therefore appears to us to be no exaggerated calcu- 

 lation of their probable number. 



Their geographical and local distribution, also, 

 are points to which very considerable interest at- 

 taches, the former being indicative of the effect 

 of climate and temperature upon form, as well as 

 showing how widely nature spreads some for cer- 

 tain purposes ; whereas she adopts the use of ana- 

 logical form and structure in other instances; clearly 

 showing, by this variety, that a difference of func- 

 tion is required where we do not perceive even a 

 modification of its action ; whereas their local dis- 

 tribution is evidently very intimately connected 

 with their instinct and economy in fact, wholly 

 influenced by them. The science possesses some 

 very valuable but partial contributions to both. It 

 is merely necessary to indicate Klug's description 

 of some insects from Java ; M'Leay and Horsfield's 

 Annulosa Javanica ; Savigny's admirable plates to 

 the large work on Egypt, which, if we possessed 

 the descriptions to the figures, would not be sur- 

 passed in the annals of entomology ; Palissot de 

 Beauvois' InsectesRecueillis en Afrique et en Amer- 

 ique; Spixand Martius' Delectus Animalium Articu- 

 latorum, and, as an example of assiduity and la- 

 bour, displaying the richness of the Fauna Insec- 

 torum of a single country, we should look in vain 

 for a more valuable one than is to be found in 

 Stephens' " Illustration of British Entomology." 



Our systems are essentially artificial, and must 



