b.7-] 
PLATE ®t 
EEGs LE 
MONOCULUS QUADRICORNIS. 
APTERA. 
GENERIC CHARACTER. 
Legs from four to eight, formed for {wimming, and very long + 
body covered by a fhell divided into fegments: Antenne either four, 
two, or none; eyes one, or two, approximate. and fixed in the fhell : 
feelers four, and in continual motion when {wimming : pofterior ones 
very {mall and hooked. 
SPHLOITIC CHARACTER: 
Antennze four : tail ftraight and bifid ; the divifions ramofe. 
Although this infeét may have been noticed by many, fwimming, or 
rather darting {wiftly in various direétions in water; its minutenefs is 
fuch, that the moft attentive could never have comprehended precifely 
its component parts. The microfcope difcovers it to be an animal 
of fuch fingular formation as highly to deferve the attention of the 
naturalift. It is covered by a hard fhelly fubftance, divided into 
annulations, and armed in feveral parts with {pines aud briftles; not- 
withftanding which, this fhell is fo tranfparent that the whole motion 
of the inteftines is very vifible by a good magnifier. 
B4 it 
