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Show 17,8 0f the Creeping of Aimztlr. Chap. X XI I I, Pofitions, mol'c proper and agreeable to this Flufiuating Motion (as very eafie to Reptiles) which is exerted in hollow Flexures, made by Contra. filed Mufcles in one fide, relaxing the Antagonilts of the other, modelled into a convex Pofiure; whereupon the Mufcles of each fide being recipro. cally contracted, and relaxed in Motion and Rel't, do alternately make v1. rious Mazanders in their concave and convex Surfaces, in order to transfer their long (lender Bodies piece by piece, from place to place, by many fuc.‘ ccflive fegnients of Circles, telling upon divers centers of Motion, very vilible in Reptiles; as Snakes, Vipers, Glow-worms, and the. like, which are not only drelfed with Lateral, but alfo with Mufcles, taking their rife from the Neck, and inferred into the pol‘terior region of the Head, which being Contraéied, lift up their alternate arched Motion, whofe intermedial points are kept in a right pollute with the Head, always conferved directly forth-right, while the Body fporteth tit felf on each fide, in various fucceifive fegments of Circles, in reference to Progreflive Motion. And in relation to repofe, Serpents have their Heads enwrapped‘ within many fegments of Circles, produced by a general Contraction of all the Mufcles relating to one fide, drawing all the Vertebres of the Back in a circumference toward the Head; whereupon all the Mufcles of one fide be- ing Contracted, their Antagonifls are Relaxed, and the whole Body is moulded into Spires, every way encircling the Head. Undulatirm Thus far of the firfi kind of motion proper to Reptiles, called [Indulagcfgflofl'g‘,‘ tion , moll: confpicuous in Serpents, Snakes, and the like; whofe long milki- Bodies are wheeled this and that way in quicker Motions ; whereas the fe~ cond degree of Motion Riled Creeping, is more flow and fucceflive, whereThe fccond in the Fluetuation of the Body is made by bending not {ide-ways, but up 521533331; ward: So that fome part of the Body is acted with Motion (while the ilFlummon- other is compofed to tell) in various Poltures, fucceeding each other, plain- ly difcernable in Silk-worms, which are for before and behind with fuch fmall Feet, ( that they can fcarce be difcovered) and between them is feat- ed fo large an Interval, that their Bellies touch the Ground in Motion, which is accomplilhed by divers Mufcles ; fome placed in the Back, others in the Sides ( terminating in the Annular Fibres) which being Contracted toward the Head, and thofe of the Back making Flexures upward in it, do draw the Body forward toward the Head ', fo that rel‘ting the Poflerior part of their Body on the hinder Legs, Silk-worms pull themfelves forward, by forming divers Arches in the Intermedial parts, which being afterward di- Thcthirdkind of motion in lupin? is fiendcd, their Bodies are reduced into fitaight Pofiures. Other Reptiles, as Leeches and Worms, have another k ind of Progteflive Creeping Motion, which is not efl'céted either by moving laterally or made yEXv "mam", upward by various Flexures, but long-ways and fhort-ways by Extenfio n Comflmcm- and Contraétion, produced by Minute Fibres, as Tenfors rendring there Infefls more long and (lender; and by other Fibres, as Contract king the parts more thick and lhort, by whofe joint aflifiance ofors, maTenfors and Contraé'rors, the bodies of Leeches and Worms are drawn their Anterior parts firlt, the Center Motion refiing in their forward in hinder parts, which at that moment are thickned and immovea ble, and afierward move, while they grow long and flender by Tenfors: So that Ed} the Anterior parts of thefe Reptiles are leifened, and moved, and the hinder parts are immoveable as Hypomoclia, and afterward the Pol'terio r and the Anterior is thickned, being rendred the Center ofRegion is lelfeneda Motion: upon ( I conceive) the Motion of thefe Reptiles is celebrated by Wheredifferent chap. xx 11 1. 0f the Creeping of flnima/r. Fibres, as Extenfors and Contractors; the firl't playing in the Anterior parts, draw them out in lcngtlr and afterward being fliortncd into a greater thickn nefs bv Contractors, pull the Body toward the Head; fo that the Anterior parts being Incrailated and illortned, the Pofterior are made {lender and lengthned by Tenfors, and afterward reduced by Contractors more clolely into th/ mfelves, pull the Pofierior parts forward. Nature, God's V icegerent, ufeth divers Methods in the conduit of Proorellive Motion, and as it is more Excellent, it bath a better Apparan :15 , made of a more perfeét and greater number of Infirumcnts, more choice Bones, and better contrived Articulations, and more regular Mufcles, the chief Engines of Motion. \Vherefore, the methods of local Motion in lotver ranks of Animals, as Infté‘rs, and the like, are very obfcure and imperfect, as gradually celebrated \Vi.h more llownefs, wherein the whole Body is not moved at once, but one part after another with great induflzry and time, which is performed in ob" lique {lender Bodies, not fupported by the interpolition of Articulated ] imbg, as {0 many Jointed Columns, but often Sweeping or Creeping upon {bmu Area, \Vltl') their bare Bellies, which in feveral parts are lifted up and depmfed again to the Ground, to draw the Body piece by piece from place ‘ to plice. Btfore we make any farther progrels, it may feem Methodical to be inqnifitive into the nature of this Creeping Motion, which may be worth out Time, as well as Pains, as being a matter of great Curiofity and Wonder, to undetliand the great Works of the Creator, in reference to the molt Minute Creatures. And indeed it is very diflicult to apprehend the Method by which Nature proceedeth, in the produé'tion of Motion relating to Infecis, which is much different from that of greater and more perfect Animals, and is not at all relating to Walking, Flying, Swimming, which require a greater Apparatus of more noble Organs: Again, the conception of this Motion, is perplext in point of its Various Modes, as Spiral, Arch-like, G‘Jc. Thirdly, It is difficult to pry into the Nature of it, becaufe the Infiru~ ments of it are not very obvious to Senfe, by reafon of their fmallnefs, imperfection, and various confufed parts; f0 that fome Animals are furnilhed in order to this Creeping Motion, with Bones, Joints, and Mufcles, the main lnflruments of Motion, as Eels and Serpents; but in other Animals they are deficient, as Leeches and Worms, and the like, and have neither Bones nor Joints, but finall Annular Membranes in ftead of Bones, and firaight Fibres in Head of Mufcles. And now I will take the freedom to offer fome requilite Conditions, found If): ffgn‘fif'és in Minute Animals, as {0 many Pillars, upon which all Creeping Motion is iswavdikC- built ; The firft is fome iinmoveable Bafe or Area ( upon which this Mo- Tm mm tion is founded) featcd without the moved bodies of Animals, which are 2331;; g," the fiibjeéls of Motion, and are the fecond requifite of it, and the third and Spire». chief are the Machines, or inltrumental caufes of this Motion. Local Motion, commonly called Creeping, admitreth a Divifion into Them", ,5 many kinds, as {0 many Modes of it, which is fometimes Wavelike, di- cchfled iiy Vcrlly celebrated; as when the Back is curled above in variety of illort $3353; Waves, which is evident in Leeches, and Silk-Worms; or acted below, when Oblong bodies are rendred Crooked, part after part fuccellively, wherein the Body is moved by degrees, by Spire after Spire, from Term to Term, as in Lampreys, Eels, Congers: But Infeéts do extend firft the Mm Fibres, fore |
