THE AMERICAN ENTOMOLOGIST. 



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lueiits, the latter correctly remarking that "none 

 but social insects feed their larvre periodically.* 

 Strictly speaking, the Digger Wasps do not feed 

 their larvje at all. They collect suitable food 

 into a suitable nest, lay an egg therein, close up 

 the nest, and then leave it forever. As a general 

 rule, it is only the higher animals that feed aiul 

 tend their young after they are born. All mam- 

 mals, and almost all birds do this, while it is done 

 by but very few reptiles and by still fewer fishes. 

 Consequently, as the Social Insects (Honey-bees, 

 Hornets, Yellow-jackets, Auts and White Ants) 

 have this propensity, and, as any one may see 

 by disturbing an Ant's nest, are as much attached 

 to tlieir larvie as a mother is to her child, we 

 may justly, so far an t/iis character goes, consider 

 them as superior to other insects. But any mode 

 ol classification, founded exclusively upon this 

 one single character, would be open to the same 

 objection as certain modern Systems of Classifi- 

 cation broached of late years in this country, and 

 founded exclusively upon a single character; 

 namely, that they are artificial and not natural 

 systems. 



It may not be amiss to remark here, tliat 

 there is a samll group of Digger AVasps (Mutilla 

 ^ub-fanlily ), the females of which have not even 

 the slightest vestiges of wings, and strongly re- 

 semble ants, for which they are often mistaken 

 by youug entomologists. They may be distin- 

 guished, however, at once from any of the Ants 

 by their antennre not being flail-shaped, or''geni- 

 culate " as it is tcehiiicallj^ termed. From the 

 great dissimilarity of the females to the males, 

 some excellent entomologists were formerly in 

 certain cases deceived into referring the two 

 sexes, not only to distinct species but to distinct 

 genera ; and the very same thing has occurred 

 with another genus {Myzine) belonging to an 

 allied group {Scoliu family), where the sexes 

 are indeed both of them winged, but difl'er 

 widely from each other in certain structural 

 peculiarities. Through the kindness of Dr. 

 I'lummer, of Rock Island, Ills., who served in 

 the medical corps of our army during the late 

 war, we received several years ago from the 

 State of Jlississippi a large scarlet and black 

 species of this sub-family, about three-quarters 

 of an inch long (Mutilla coccinea, Fabr.), the 

 sting of which is said to be peculiarly powerful 

 and virulent in its eftects. The females of those 

 species, which have been seen by us when alive, 

 are always found in sandy localities running 

 about like ants; and such is said to be the gen- 

 eral habit of the whole group. The males 



occur on flowers and shrubbery, and are very 

 difficult to identify with their appropriate fe- 

 males, uidess actually taken in copulation. 



Although so snugly secluded from the world 

 — each in his own i)rivate and peculiar cell, and 

 with an abundant supply of delicious insect- 

 meat close to his very mouth — the larvffi of the 

 Digger Wasps do not escape the attacks of those 

 universal marauders, the Ichneumon-flies and 

 their allies. For example, besides the two 

 parasites already referred to above as infesting 

 the little mud-daubers (Agenia), a beautiful 

 Ichneumon-fly {Cryptiis jinicens. Cresson) — 

 represented in Figure 109 ( $ ) and remarkable 

 for having when alive the peculiar and to us very 



[Fig. 1(19. 



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agreeable smell 

 of a Humble-bee 

 (J9omJi«s)— oft- 

 en pierces with 

 its long tail-like 

 ovipositor our 

 common large 

 " mud - dabs, "' 

 and deposits an 

 egg in the car- 

 cass of the un- 

 fortunate larva 

 of the Mud-dau- 

 Colors— Black ;iml yellow ber. From this 



egg the larva very soon afterwards hatches out 

 and finally, as usual, consumes the vitals of its 

 victim, and subsequently spins itself up in a co- 

 coon. We have ourselves bred the above Iclmeu- 

 mon-fly from these "mud-dabs," and have repeat- 

 edly found its thin white silken cocoon, with the 

 larva inside it, in the clay-cell of the Mud-dauber. 

 Thus the spider preys upon flies, the mud-dau- 

 ber upon the spider, and the ichneumon-fly upon 

 the mud-dauber. " Kill atid be killed ; eat and 

 be eaten." This is tlie great universal law" of 

 Nature. Every insect is checked and controlled 

 by the attacks of others. None, as a general 

 rule, except when man by his artificial processes 

 interferes with the wise arrangements of 

 Nature, is ever allowed to become unduly nu- 

 merous. Every being in the world, not exclud- 

 ing even the human species, exists, not only for 

 its own pleasure and benefit, but for the plea- 

 sure and benefit of other and often very inferior 

 animals. Nothing in nature exists for itself 

 alone; nothing is wasted. Even the dried uj) 

 remains of the doomed spiders, upon which the 

 larva of the Mud-dauber has fed, are not allowed 

 to goto waste; but are preyed upon quite ex- 

 tensively by the larva of a small beetle {Tro 

 goderma ornatum, Say), belonging to a 

 Family (Dermestes), several species of which 



