. j The Water-Flea with branched Horns. 305 
Behind the abovementioned Gut, and as 
it were detached from the reft of the Body* 
j * 
the Heart is placed, and may be feen dilat¬ 
ing and contracting, alternately, with a very 
regular and diftinCt Syftole and Diaftole. 
The lower Part of the Shell terminates 
in a long Spike or Tail, which is without 
Motion, but thickly fet with fix Rows of 
fhort ftrong Spines, making its Appearance 
like the prickly Horn or Snout between the 
Eyes of Lobfters, Cray Fi/h, Shrimps, &c. 
Swammerdam has very judicioufly ob- 
ferved * (what every Body who examines 
it carefully will difcover to be true) that this 
Animal has three different Kinds of Motion. 
The firft is a fmooth and even fwimming, 
whereby it carries itfelf horizontally along 
in the Water. The fecond is a fudden /kip¬ 
ping or leaping, much refembling that of a 
Flea. And the third is, when lying at the 
Bottom of the Water, it turns its whole 
Body round as it were on a Center, with a 
very bri/k Rotation, by Means of its fmall 
Legs or Fins. ^ 
As no Creature lives without its Tormen¬ 
tors, this is very much infefted by the Shelled 
Wheel Animal already defcribed. Page 298, 
and fhewn in the Plate, with this 9 Jig. 7, 8, 9. 
Both thefe In feds are in great Abundance 
frequently in the fame Water; and when that 
* Hill. Gen. des Infe&es, p, 69, 70^ 
Vol. II. X 
IS 
