Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/655

 T I P

T I R

fame line with the body, and is {lender, and compofed of fe- veral fcaly parts, proceeding from the laft ring of the body. Thefe creatures are found in our meadows through the whole fummer ; but the end of September and beginning of Octo- ber is the time when they are moft of all plentiful : They are fo common in fome meadows, in thefe months, that there is no walking a ftep without putting up whole flights of them. They are extremely well furnifhed by nature either for walk- ing or flying. In the middle of a hot day they will often rife to a great height in the air, and take long flights ; but at other times they ufually only fly to one part of a field from another. They fometimes ufe their wings alfo in the manner of the oftricb, aflifting their leg. 1 : with them in running; and fometimes they make no fmall ufe of their legs in their Ihort flights, the fpring with which they throw thcmfelves off from a plant, carrying them to half the diftance they are going to.

The legs of thefe creatures are greatly difproportloned to the body, according to the common rules of nature, efpecially the hinder pair, which are in the larger fpecies ufually three times the length of the body. Thefe carry them fafely and eafily among the plants, and feem of the fame ufe to them that ftilts are to boys, in wading through dirt. This large (pedes is a creature of no great beauty. Its body is of a brownifli colour, and its corcelet is fo elevated, that the crea- ture feems hump-backed. The head is fmall, and the neck very Ihort. The reticulated eyes are fo large, that they cover aimoft the whole furface of the head ; thefe are of a greenim colour, with a caff of purple, when viewed in fome lights. Mr. Reaumur very carefully examined the head, to find out fome of thofe fmaller mining eyes which other infects of the fly kind have, and which refemble thofe of fptders : Thefe are ufually placed in a triangular figure on the head ; but in this creature there are none of them in the common place ; there appear indeed two lucid fpecks, one at the origin of each of the antenna?, when the head is carefully examined with a mi- crofcope : But Reaumur does not allow thefe to be eyss, he rather fuppofes that two very lucid fpecks, on the anterior part of the breaft, are eyes, though placed in fo very fingular a manner. The wings of this creature are long, but very narrow, and feem fcarce well proportioned to the fize of the animal; they are tranfparent, but have a flight call of brown; and their ribs, when viewed by the microfcope, appear befet with fcales, or feathers, in the manner of thofe of the gnat kind. Some fpecies of the Tipula have them alfo fringed, with thefe fcales at the edges. There are no ailerons, or petty- wings, at the origin of thefe, as is the cafe in many of the other fpecies of two-winged flies ; but in the place of them there are two very fine balancers or mallets. Thefe have long pedicles, and roundifh or oval heads. The ftigmata of the corcelet are four ; one pair are placed immediately underneath thefe balancers, and the other immediately below the firft pair of legs. The firft pair are very long, the others fmall, and thofe on the rings of the body, if there be any, are too fmall for our fight, even with good glaffes. Each ring of the body is compofed of two half cylinders, which are joined into one, by means of a membrane, which gives them room to diftend or clofe up at the creature's pleafure. The large Tipula all carry two antennae, or horns, upon their head ; but thefe are of no remarkable ftructure, they are only com- pofed of a great number of joints, each covered with a fine downy hairynefs ; and at the joining of each to the next, there is a tuft of longer and more ftift'hairs. This is the defcription of the common large bifida which we find in the meadows ; and in aimoft ali its parts, is applicable to the generality of the larger fpecies of thefe infects. Reaumur, Hift. Inf. vol. 9,

I he fmaller kinds are very numerous, and of great variety. Thefe are frequent m all places, and at all feafons of the year : The fpring fhews us immenfe clouds of them, and even the coldeft winter's day fhews a great number of them in the fun- fhine about noon. Thefe creatures fly much better than the large Tipula ; they feem indeed to be aimoft continually upon the wing, and their manner of flight is very fingular ; they are continually mounting and defcending again, and that without quitting the direction of the line they go forward in ; this they will often do for many hours together. In tracing thefe flies from their origin, they are all found to be produced from worms which have no legs, and have a regular fcaly head. Thofe from which the larger Tipula are produced, live under ground ; they are moft fond of marfhy places ; but any ground will do that is not often difturbed. They ufually are found at about an inch under the furface, and are fo plentiful in fome places, as greatly to injure the herbage. When they get into corn-fields, they caufe whole acres of the corn to wi- ther before it grows into the ear, and even inpafture-land the grafs is fometimes fo entirely deftroyed by them, that there is no food for cattle in places where the herbage ufed to be ever fo plentiful and ftrong. It has been fuppofed from this, that they eat up the roots of the plants ; but this is not the cafe ; they feed only on the fmall infects which live under ground, and take in a large quantity of dirt with them into their fto- machs. The mifchief they do, is by their being continually in motion, and loofening by this means the earth from about

the roots, fo that they dry up with the fucceeding heat of the fun.

Thefe creatures do not find it neceflary to their living, that plants mould he upon the furface of the earth in which they live. There is frequently found in the hollows of the flumps of old trees, a fort of earth which feldom produces any vege- tables ; yet the female flies of this fpecies well know that their young will find a proper fubftance there J and there are ufually found great numbers of them in all thefe places. The hollow elms and willows, fo common in our hedges, and by ditch- fides, afford innumerable proofs of this : but it muft be ob- ferved, that they are only found in fuch earth of this kind, as is continually fomewhat moift ; that is, fuch as is placed in a cavity which will retain the wet that falls into it ; for when the earth lies in places where the water eafily drains off, there never are found any of thefe infects in it. Mr. Reaumur mentions a very fingular fpecies of large Tipula, which was produced with him from one of the worms found in the earth of an old elm ; this was of the larger kind, and had fome beautiful fpots on the wings. It had alfo very elegant tufted antennre ; whereas, in the common large Tipula, thefe are plain and fimply granulated ones, as well in the males as fe- males. Reaumur's Hift. Inf. vol.9. P' *7* Mr. Rav, in his hiftory of infects, defcribes fourteen fpecies of this fly found in England. I. The common Long-legs. This is about an inch long, and its antennae are ihort and {lender, and its eyes black. The male of this fpecies is more obtufe at the tail than the female. 2. A very large kind, with large wings fpotted with brown and white. 3. A large kind, with two large black fpots on the wings. 4. A very beautiful Tipula, with black moulders and back, a yellow belly, and fome brown fpots on the wings. 5. The yellow- winged Tipula, with fpots on the wings, and a black and yellow body. 6. The common fmall Tipula, with brown wings, fpotted with white, and with opake dark brown ribs. 7. The middle- fized black and yellow Tipula. 8. The long-legged Tipula, with (hining black eyes. 9. 7'he fmall purple-winged Tipula, with a black back and yellow belly. 10. The middle- fized green-eyed Tipula. 11. The brown- ifh-grey Tipula, with extremely long antennae. 12. The elegant Tipula, with plumofe antennas. 13. The fmall Ti- pula, with brown wings ftreaked with black. And 14. The fmall Tipula, with ftriated wings, each having one very large black fpot near the end. Ray's Hift. Inf. p. 72. The white Tipula is a very beautiful little infect ; it is very common in gardens, and among bufhes in September and October ; and tho* it appears all over white when feen at a diftance, yet is not found to be fo when examined more nearly. The wings, when the creature is fitting, cover the whole body, and thefe are white ; but the body itfelf is of a yellowifh-green m that part next the head, and of a brownifh- black in the hinder part. The head of this creature is very fmall, but the antennae, or horns, are extremely long, and very beautifully feathered ; they feem indeed a load to the creature to carry, and in their ufual pofition are crofted one over the other in fuch a manner, as to appear only one body together. Reaumur, Hift. Inf. vol. 9. p. 20. TIRATA, in the Italian mufic, is ufed to exprefs, in general, any quantity of notes, of whatever kind, provided they be of equal value, moving either upwards or downwards in con- joint degrees ; thus they fay, Tirata di Semimin'wie, when there are many crochets following one another in the manner above mentionod ; Tirata di Legature, when there are many notes of the fame value following one another, among which the laft of one bar, and the firft of the next, are tied together by a femicircle, thus ; •-. — - or - — --,.

Tirata is particularly ufed for a feries of quavers, or, in the modern notation, of demi- quavers or demi-femi-quavers 3 af- cending or defcending by gradual intervals. Thefe Tirate often, tho' not neceffarily, begin with an unac- cented note, and end on fome accented one of greater dura- tion. See the example annexed.

Muficians diftinguiDi feveral kinds of Tirate, thus :

1. Tirata mezza, or mezza Tirata, is that compofed of three or four quick notes to afcend, or defcend to a note, a fourth, or fifth, higher or lower than the note from whence the Ti- rata begins ; as in the examples before given.

2. Tirata defetfiva is when thefe running notes go beyond the fifth, but do not reach the octave.

3. Tirata pcrfefia, is when it runs through the notes of a whole octave, afcending or defcending.

4. Tirata autta, or excedem is when it goes beyond the com- pafs of an octave.

The French call the Tirata, Tirade, and fome call them raw lodes, but improperly, fays Brofiard. TIRSIO, in ichthyology, a name given by Gaza and fome other authors to the phocsna of Willughby and others, the porpeffe, or marfuin. It is a fpecies of the delphinus, ac- cording to the Artedian fyftem ; and is called the dolphin with a conic mapedbedy, a broad back, and a Iharp fnout. Pliny,

Bella-