Packard.] 292' 



less, and have to be fed by the prevision of the parents. In undergoing 

 a more complete metamorphosis than any other insects, in the unusual 

 differentiation of the sex into males and females and sterile females, or 

 workers ; with a further dimorphism of these three sexual forms, 

 and a consequent subdivision of labor among them ; in dwelling in 

 large colonies, thus involving new and intricate relations between the 

 individuals of the species and other insects, their wonderful instincts, 

 their living on the sweets and pollen of flowers, and not being carnivo- 

 rous in their habits, as are the Neuroptera, and a large proportion of the 

 Orthoptera, Hemiptera, Coleoptera and Diptera, and their relation to 

 man as a domestic animal, subservient to his wants, — the bees, and 

 hymenoptera in general, possess a combination of characters which are 

 not found existing in any other suborder of insects, and which we must 

 believe, rank them first and highest in the insect series. 



Likewise the hymenoptera are more purely terrestrial insects than 

 all others. The Neuroptera are, as a whole, water insects, their larvae 

 live in the water, and the perfect insects live near streams and pools ; 

 the Orthoptera are more terrestrial ; among the Hemiptera are numer- 

 ous aquatic species, as there are in all the other suborders except the 

 hymenoptera, of which only two genera are found swimming in the 

 adult state on the surface of pools, and they are the low minute Proc- 

 totrupids, Prestwichia natans and Polynema natans Lubbock. As we 

 have previously shown, the Hymenoptera do not imitate or mimic the 

 forms of other insects, but on the contrary, their forms are extensively 

 copied in the Lepidoptera and Diptera especially. There are synthetic 

 types or mimetic forms which bind these suborders into a single series. 

 As the Coleoptera, Hemiptera, Orthoptera and Keuroptera are bound 

 together by homomorphous or mimetic forms into a series by themselves, 

 so the Hymenoptera, Lepidoptera and Diptera, possess their synthetic 

 types linking them together. 



Another and very accurate method of determining the relative rank 

 of the larger groups in nature, is by comparing the degradational 

 forms occurring in each group. Among the Neuroptera the lowest 

 wingless forms, such as Lepisma and allies, most strikingly resemble 

 the myriapods, in the great equahty in the size of the arthromeres 

 composing the body, and the slight distinctions preserved between 

 the three regions into which the body is divided. The largest, most 

 vegetative, monstrous and bizarre forms of insects are found among 

 the Neuroptera and Orthoptera. Among Hemiptera the parasitic 

 wingless lice, and among Coleoptera the low Meloe and Stylopldaa, 

 afibrd instances of a genuine complete parasitism such as obtains 

 more fully among the low Crustacea and worms. While we find the 

 degraded types of insects belonging to the lower series of suborders, 

 present elongated, worm-like, myriapodous forms, in ascending to the 



