Of the Wheel Animal . 283 
feem intended to propel their Contents 
downwards. Around the Bowels are many 
Ramifications of VefTels both longitudinal 
and tranfverfe; and between the Bowels 
and the Skin a Fluid exceedingly tranfparent 
fluctuates in a Manner Words cannot de- 
fcribe. 
The Belly is capable of ftretching out 
greatly in Length, or being fhortened very 
much and widening its Diameter : in fhort, 
it aflumes many Shapes, and becomes, on 
Occaflon, a Cafe including the whole Ani¬ 
mal, as will by and by be lhewn. 
From a Joint at the lower Part of the Belly 
to the pofterior Extremity is what I call the 
Tail. (Vid.Jig. 5. g.J It has three other 
joints, to the lowermoft whereof the Bowels 
extend themfelves, and appear contra&ing 
and dilating upwards and downwards, tho* 
not fo remarkably when they are empty as 
full. This Part runs tapering from the 
Belly to its End, and is lengthened or fhort¬ 
ened at the Creature’s Will. When it is in¬ 
clined to fix itfelf by the Tail to any Thing 
(as commonly is its Way when it intends 
to work with its Wheels) two, four, and 
fometimes fix little tranfparent Hooks or 
Fins may be feen thruffc out at its End, and 
ferving for that Purpofe. They are placed in 
Pairs : one Pair is at the very Extremity, and 
the other two a little Way up the Sides ; but 
the three Pair are feldom feen together. 
Though 
