Of the Wheel Animal. 273 
Head down, and drawing up the Tail 
to it. 
Fig. 3. exhibits the Infedt with its two 
femi-circular Parts put out, and'exad:- 
!y in the Poflure it places itfelf, when 
it prepares either to fwim away, or to 
fallen by the Tail and work its Wheels 
about. 
The general Account already given, will, 
it is hoped, render my Talk the eafier, now 
I come to examine the mod: diftinguifhing 
Parts of this Animal ; viz. the Head , the 
\Thorax or Breafi , the Abdomen or Belly , and 
the Fail: each whereof I fhall defcribe with 
all the Perfpicuity and Brevity the Subject 
will allow. 
The Falhion and Conftrudfcure of the Head 
is wonderful, and extremely different from 
that of any other Creature hitherto defend¬ 
ed ; its hidden Change out of one Form 
into another is alfo unufual and furprizing : 
for, from being perfectly tapering, and end¬ 
ing almoft in a fharp Point, like the Plead of 
a common Maggot, it becomes on a fudjden 
as wide as ahy Part of the whole Infeoc, 
opens a large Mouth, and is furnifhed by 
Nature with an amazing Piece of Machine¬ 
ry whereby to procure its Food. 
One of thefe Animals, with the Head^as 
here deferibed, is reprefented fig. 4. where 
a Couple of circular Bodies, armed with 
final! Teeth like thofe of the Balance-Wheel 
Vol. IL T of 
