FLY. 769 FLY. species, and in number of individuals it is un- excelled by any cither group of in eel from the prolificacy and rapid breeding oi the man; forms. Some curious biological ph ins oci ur in this group. In a great main lie , for example, the hatch within the bodj of the insect, and the living larva: are deposited. With the group known as the Pupifera, even the larva] develoj ml is undergone in the bodj of I he fi ma le, and t he insect is deposited in the pupa] condition. The extraordinary phenomenon known as psedogene i also occurs, and the larvae of a certain midge are known to give birth to young while ye] in the larval condition. The metamorphoses of dip- terous insects arc more complete than those of any other order of insects. The larva is com- monly termed a grub, or maggot, and is fiint less and frequently almost structureless. In mans species lie- dura tion nf the larva I stage i verj -hmt. The maggo] feeds voraciously, grows with ct raordinary rapid- ity, and transforms to pupa either within the las] larva] skin or into an appendage hearing pupa similar In thai of certain Hymenoptera or l.epidoptera. The differ- ent forms vary greatly in habits. Very many are feeders on decaying animal and vegetable mat- ter. Others arc pa ra-itos (in warm-blooded animals. Many forms are aquatic. •SrobSsci* "' labh ' m ° r othera feed "I"" 1 'Mug vegetation, while others form galls upon clill'erent plants. Among the plant-feeding flies, some species have high rank as injurious insects, as the Hessian My and the onion-maggot, the apple-maggot, and others, while whole regions are rendered almost uninhabitable by the presence of forms which annoj men and animals. Habits and Economy. Adult dies vary greal ]y in structure and in habits. With some the mouth parts are tilled for piercing the skin of warm-blooded animals — the mosquitoes and the gadflies, for example, are especial torments of men and animals. The discovery that certain dipterous insects are important factors in the transfer of disease has rendered them the sub- ject of special study of late years. The function of certain mosquitoes in the transfer of yellow- fever and malaria, the transfer of anthrax bj certain gadflies, the carriage of the germs of an African fever by the tsetse fly, the conveying of the germs of the purulent ophthalmia of the Eyptians am] Fiji Islanders by the house-fly, the transfer of the germs of typhoid fever and cholera by Hies, ami the spread of the disease known as pinkeye in the Southern Stair- bj midges, are all instance- of this maleficent func- tion. Detailed information may be found in Howard. Carriage of Disease '>» Flies (Agricul- tural Department, Washington, 1901). On the other hand, the Diptera do perform, in many cases. beneficent services to their fellow crea- tures. Many forms frequent flowers, and are im- portant agencies in the cross fertilization of plants. Edible Flies. That tlies should furnish hu- HEAD OF A FLY. Musca vomitoria : E ■eye; t, antennas; ra, maxil lary 'proboscis.' ii d i om oi i ! " their history. Small pecie of the trypetine genua I I' 1 - dra, allied to 1 1„- el e )l ipjx i Ikaline lake- of i he westei n i nited and Mej ico in enoi n m ; i i I lie case in Lake Mono, I iter is o den e « ith alt the no I h oi amphibia live in ii I hi l |' 1 ' <! ra flii resort there in countless -mum-, dro] i ad the larva? di relop - nun Ij i bal i hi | drifl in heap along I he shore, and -it i he propi i used to be gathered for food bj the Indians, who would come Ii lists nee for I he pui | a le. 'I he grub were dried in the 8iui on and then rubbed in the hand- to remove the shell, when there remained a yellowish kernel like a "i .i ni "f rii e. ul i ound tin.- a mi into cakes. This t I, called koo-chah- bee, i- oily, nutritious, and not imp lea -am in taste. The species i- Ephydi a Californica imilai ration, under the name of nhimlh. i- m.ob- from the i — of Ephydra hians in Mi ico These eggs a re laid on sedges, w hich 1 1 about Lake Texcuco purposely set afloat. I he i inn collected and beaten over a dot ; gS oil', which arc I hen cleaned and into a Hour. The larva of these Hi'-- are also eaten under I he m of p Classification. The difficulties in the -ys- tematic study of the Diptera are verj and iii many groups the s] number of families have not been well worked up i a count of the difficulty of preserving -imc they are so slender and fragile. Il i- prob- able that not more than a quarter of (he in existence have been named and classified, and Dr. Howard estimate- thai the order includes no less than 350,000 species. The latest compre- . FLY. The adult bouse-flj {Mutica domestics,) and Itsfull-grown larva. hensive study in this direction ha- luce by M. D. Coquillett, of the I nited stale- De- partment of Agriculture, who divides the order info two suborders; I. Epi hlg only the parasitic pupiparous families 1 1 ippobosi ii Fly) and Nycteribiidas (bat-ticks), whosi boscis i never furnished with terminal lip-: and II. Probosddea, embracing all cither llie- never parasitic on mammals, bird-, or honey bee-, and having the proboscis terminating in lips, and oviparous or Ian ipa rous. In the suborder Prol tions— i 1 )Orthorhapha and (2) Cyi lot In the tir-t are placed SUCh slender, eloti often long legged groups as t he crane-flies, midges, moth flies, snipe-flies, and gnats, to-
