COMl'AKATIVK ANATu.MV. 



COMPARATIVE ANATOMY. XI. 



I CLASSIFICATION. 



ENTOMOLOGY, or the study of insects, haa always been a 

 fnvourite branch of natural hNtory. '1'ho groat beauty, both of 

 form an- 1 colouring, to be found in many of the species of thin 

 class has always commended it to the attention of all who havo 

 any bent towards such studies. Probably the hues of the 

 gorget i u Imttcrlly, or the elegance and graceful ao- 



( the dragon-fly, have boon the first incitement to many 

 ti youth to the study of living creatures. Besides these, many 

 thousands who have no claim to be called naturalists havo 

 found great pleasure in collecting and preserving insects. " A 

 thing of beauty is a joy for ever," and whether the external 



of insects, to have expended bar most exquisite workmanship 

 in the architecture of their superficies, or the boundary between 

 themselves and the outer world. The character, the capabilities, 

 mi I tho efficiency of insect* depend mainly on the framework 

 of thrir external caning. This external caning it the relating 

 and supporting structure upon which all the soft parta are 

 built. From this peculiarity of structure it follows that when 

 an insect is dried when the muscle* havo withered and it* 

 nervous, nutritive, and reproductive organs have shrivelled 

 or decayed since they are all internal, not only is it* beauty 

 left intact, but all tho essential features by which it* habit* 

 and relationships may be determined are undestroyed. More- 

 over, it is found that when any class has any great pecu- 

 liarity, any part specially well developed, the modifications of 



v 10. 



iriEiiA : 1, CICADA (AN HOMOPTEROUS INSECT); 2, HALTS; 3, HYDHO.SIETI;A. DIPTEHA : i, ASILUS CKABKONIFOKMIS ; 5, EKISTAUS. 

 LEPIDOPTEKA : 6, EUCLIDIA Mi. HTMENOPTEKA.- 7, APATHUS ; 8, As ICHNEUMON FLY. COLEOPTEBJ. : 9, CICINDELA; 10, GEOTBUPKS. 

 NEUKOPTEBA : 11, PHUYGANEA. OKTHOPTEKA : 12, MANTIS BELIGIOSA. 



stamp of excellence called beauty induces men to examine and 

 appreciate the other excellences of Nature or not, it is good that 

 the great God should receive the praise of a thousand joyous 

 hearts for this alone. The collection and study of insects is 

 pursued with greater ease than that of any other class. Found 

 everywhere in almost infinite variety, they offer an unlimited 

 field in which every lover of Nature can occupy himself. Their 

 size, ranging as it does between a very few inches in length 

 down to an almost limitless minuteness, enables them to be 

 stored, notwithstanding their great multitude, in a space which 

 is at the command of every one. All these facilities for the 

 collection and study of insects would, however, be nugatory 

 if it were not for the peculiarities of their structure. As we 

 have seen in our last lesson, the great peculiarity and excellence 

 of insects is the perfection of the organs of relation, as they 

 are called. By organs of relation is meant the organs through 

 which the animal acts upon, or is brought into contact with, the 

 outer world, such as organs of sense, locomotion, and prehen- 

 sion ; of attack and defence. Hence Nature seems, in the case 



55 N.E. 



that part furnish the best means of classifying the members 

 of that class into minor divisions. Thus, the gills of fish, the 

 breast-bone of birds, and the intra-nterine connection of mother 

 and offspring in brutes, all of which are peculiar or peculiarly 

 developed structures, are made use of severally to divide fish, 

 birds, and brutes into minor sub-divisions. Hence it follows 

 that though in our insect cabinets we have only the dry and 

 lifeless husks of insects, yet we have in them a means of com- 

 paring and classifying insects which probably would not be 

 much increased if the whole of the organs were preserved. 

 These advantages have no doubt largely tended to make the 

 study of entomology popular. A class which can be studied 

 with any degree of completeness without recourse to the diffi- 

 cult process of dissection, is sure to receive attention. A simple 

 lens, or at most a microscope of low power, directed upon the 

 exterior of a set specimen, is quite sufficient to determine not 

 only its place in all existing classifications, but even to furnish 

 all the information on which the reasons for the adoption of 

 the several systems of classification are based. Nevertheless, 



