Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/319

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There are two fpecies of this little fifth, the one larger, of two inches or more in length, and confiderably thick. This has but five prickles, three on the back and two on the belly : this laft is fixed to a penniform bone, very hard and ftrong ; for ln- ftead of belly-fins, this has two triangular bony laminae. It has no leaks, but its fides are defended with a bony armature, reaching from the fpincs on the back to thole on the belly. It can rail? or deprefs its fpines at pleafure. This fpecics is com- mon in our ditches j and they fometimes fwim in tmmenfe flioals together in the fea.

The other is the fmaller kind : this is fhorter and much llen- derer than the former, fo that it appears proportionably of a loneer figure, ft has ten or eleven fpines on its back, and thefe notVet in an even row, but alternately bending one to the right, the other to the left ; and it has bony laminae in- fread of belly-fins, and two fpines or prickles on them ; and one behind the anus. This fpecics has not the bony armature on its fides that the larger has. It is common in our ditchts. Ray's Ichthyol. p. 34.1. feq. ' PtrcNiTius hngus, in zoology, the name of a Weft Indian fea- fifh, caught about Chili and in fome other places, and ap- proaching in many particulars to the European fugnita. It is a fmall animal ; its body is fquare, and of a tender con- flrudt ion ; of the thicknefs of a finger, and of five, fix, or feven inches long, becoming gradually fmaller towards the tail : its fkin is ftnooth, and its back is black ; its belly yel- low: its head refembles that of the pike, but that the nofi- is fomewhat longer : it has two fins at the gills, one of a tri- angular fhape on the back; and from this to the neck there are placed a row of fifteen prickles, which bend a little back- ward, and are not connected by a membrane. On the middle of the belly it has alfo two fpines at the two fides, and one behind the anus : behind this there is a fin anfwering to that on the back, and the body is terminated by a fine fmall tail. Sehenefeldt's Hift. Pifc. Ray's Ichthyol. p. 340. PULCHER pifcis, in ichthyology, a name given by Gaza to the fifh commonly known by the name of the uranofeape, or ftar- gazer. See Uranoscopus.

It is a fpecies of the trachinus, and diftinguifhed by Artedi by the name of the trachinui, with many beards on the lower jaw. SeeTRACHlN-us PULEGIUM, pemyrcyal, in botany, &e. a name given by au- thors to the common water-mint. V id. Linneei Gen. PL p. 27 1. Tourn. Inft. Bot. p. 189. Rivin. Vol. I. p. 31, 32. See alfo the article Mentha.

Penny-royal is among the firft plants in efteem in the prefent practice, as well as in former ages, as an attenuant and uterine. It promotes the menfes, and forwards delivery. It is good in flatulencies and fiippreffions of urine, and by many is greatly recommended in dropfies, jaundices, and other chronic diftem- pers. It communicates its virtues very readily to water in in- fufion, and its fimple water drawn by the alembic, has, per- haps, more virtue than any other kept in the fhops. Its ef- fential oil is fometimes, tho' rarely, ufed in the fame inten- tions with the water. PULEX, the flea. It is to Signior Redi that we owe the true hifto ry of the generation of this common and troublefome animal. The flea lays its eggs, and from each egg is hatched a fmall worm : this worm fpins itfelf a bag of filk, in the fame man ner that the filk-worm does ; and out of this bag it comes at laft in the perfect form of a flea, as the other does in its winged ftate.

The flea depofits its eggs on the bodies of dogs, cats, and other animals, and on the clothes of men, or the beds, and other places where they flcep. Thefe eggs being round and fmooth, flip eafily down till they come into fome fold of the clothes, or fome other place, where they are hatched. In this place each egg produces a fmall white worm of a filvery ap- pearance; thefe worms feed on the white fcurfy matter which is found in great plenty on the fkins of dogs and other animals ; and they are alfo found among the folds of liunen in drawers and other placss : they are a fortnight in arriving at the full bignefs of the worm ftate, and will roll themfelves clofe up into a ball, in the manner of the wood-loufe, when touched. They foon after this fpin themfelves their web, in which they lie a fortnight, and then come out perfect /««. The flea, if examined a day or two before its full growth in the bag, is found to have all its parts and lineaments ; but it is foft and white. After this it gradually becomes hard and co- loured, and when it comes out of the bag, is as ftrong and large as it ever is to be. PuLEX-/«ten, a name given by naturalifts to a fort of worms frequently found on the leaves of ttees, where they devour the animals called paliees arborei. Vid. infra. Gf thefe there are feveral fpecies, which owe their origin to the eirgs of different creatures ; for they are none of them their ultimate ftate in this- their time of feeding. According to the different animals whofe eggs they are hatched from, thefe are of different form and ftructurc : fome are hexapodes, or endued with fix feet ; thefe belong to the beetle tribe, and finally change into beetles like the parent animal from whofe eggs they lprung : others have no legs, and are produced from the eggs of flies of tarious kinds : and finally, others are ge- nuine caterpillars, tho' fmall ; but thefe are the moft rare of all. Svppi.. Vol. II.

pUL

The two general kinds are the hexapodes, or beetle- worm^ and the apodev or fly-worms. The fly which gives origin tti the laft of thefe is a four-winged one, and takes care always to depofit her eggs in a place where tin re are plenty of the pu/iies, ufually on the fbik or young branches of a tree iri the midft of large families of them. The worm, as foon as hatched, finds iifelf in the midft of abundance of food, prey- ing at pleafure on thefe animals, which are wholly ddencelefs.; The ftalk of the elder and woodbine are frequently found co- vered over with thefe pu/ices, and among them there may ufually be found one or more of thefe deftroyers feeding at will, fucking in the juices from their bodies, and then throw- ing away the dry Ikins. Befides the worms of thjs four-winged fly. there is one of a two-winged wafp-fly, very dcftruelivc of thefe animals. Reawnur's Hift. Inf. T. j. PuLEx-ar&.reui, in natural hiftory, the name given by Mr. Reaumur to a very large genus of fmall animals. They are a kind of h.ilf-wingcd creatures; they have granulated antenna;* and fome of them, in their nioft perfect ftate, have complete: wings. Thefe are diftinguifhed from the others by the name of mujca putex, or the iv'wged-putex.

The feveral fpecies of thefe creatures are of different colours j fome are brown, others yellow ; but the moft frequent are green. They all feed upon the leaves of trees, which, become! withered and curled up on their eroding them ; and they are fo common, that where', er a leaf of a tree is found curled upj or of a different form from the others, it is highly probable thefe animals are on it, or that it is their work. Among trt.es the - willow and the rofe are the moft infected by them; and amono- plants, the bean and the poppy, They live a focud life, mul- titudes of males and females being found together. The fe- males are eafily diftinguifhed from the males, by their being thicker in the body, and having larger bellies. It is very wonderful, that' of all the known animals of the winged kind, thefe are the only ones which are viviparous. This is eafily feen beyond a pcfhbility of doubt ; for on examin- ing a duffer of them together, it is a common thing to fee, by the help of a fmall magnifier, a fimale in the ad~f of parturi- tion ; and the author of this account frequently faw the youn« pulex protruded out, from a paffage near the anus of the f .-male, perfectly formed. He had fufpeiSted this from the total want of eggs among fo numerous a tribe of animals, and from their remarkably fpeedy propagation, and was thus convinced of it by ocular demonftration.

They are armed with a tender and flexile probofcis, with which they feize hold of the young flioots of the tree : they live upon twifting the probofcis round it. 7'hefe creatures are always feen naked and expofed, ftanding on the outfide of the ftalks and leaves, and fucking in their juices for nourifh- ment with their probofcis. But there is another fpecies of them, which are alike viviparous, and agree with them in all refpecTs, except in their manner of living. Thefe get into the inner fubftance of the leaves, like the worms called ajcarides^ and feed on the parenchyma, being defended from all injuries by living between the integuments. In this cafe, the leaves they bury themfelves in become icabrous and deformed, and pro- duce a fort of galls: fo that Malpighi erred in fuppofmg all the galls of trees to be produced by the animals batched of the eggs of ichneumon flies; iince thefe animals which are vivipa- rous, and are of a very different kind from the worms of the ichneumon flies, equally produce them A female of the fpe- cies here treated of has been feen to bring forth feven young ones in one day; and thus, from refiding alone in the tuber- cles which fhe had formed on a leaf, fhe in a little time be-< comes the mother of a numerous family ; each of which raifes its own tumor or gall on the leaf, which at firft are fmall and round, and of a beautiful red like kermes. Such of thefe as are of the male fpecies have a certain time of reft, in which they lie buried in a ftlky matter, and afterwards become winged, flying nimbly about ; whereas the females never are able to fly, but remain always half-winged. It is to be obferved, however, that there is a different fpecics of wing- ed infecls frequently found flying about the female pulice!, as well as their own males ; fo that all the fmall-winged infe<5ts about them are not to be thought of their own fpecics. Thefe" do not greatly differ in figure; but the one are h rmlefs, and the others have ftings, and hurt any part of the body on which they fix. Reaumur's Hift. Inf. T. i. See PsEUDQ-puIrx. Z,0(7///a-Pui.Ex. See Cicadula.

PULMONARIA, in the Linnasan fyftcm of botahv, the name? of a genus of plants, the characters of which are thefe : the cup is acylindric, pentagonal, perianthium, confifting of one leaf divided into five fegments at the edge, and remaining after the flower is fallen. The flower confifts of one petal, in form of a cylindric tube, of the length of the cup, with its edge flightly divided into five fegments, and its mouth open. The ftamina are five very fhort filaments, fituated in the open- ing of the flower. The anthers are erecf, and converge one toward another. The piftillum has four germina. The ftyle is flender and fhorter than the cup, and the ftigma is obtufe and emarginated. The cup, without fufrering any changes, ferves in the place of a fruit, containing in its bottom four round'ifh-leaved obtufe feeds. Linn&i Gen. PI. p. 59. The characters of pulmonaria, according to Mr. Tournefort, 3 Gg are