calls it “ infedoram omnium facile maximum.” It is 
a native of the Indian ocean, and is faid to be gene¬ 
rally found in pairs, or male and female fwimming to¬ 
gether. Molt of the fpecies of Monoculus are fmall 
frefli-water infeds, and fome of them even belong to, 
the tribe of microfcopic animalcules. To thofe who 
are accuftomed to penetrate into the lefs confpicuous 
provinces of Nature, and to inveftigate the legions of 
animated beings with which the waters in particular are 
peopled, it mutt afford a pleafing entertainment to view 
feveral fpecies of this genus, which though fcarce per¬ 
ceptible without the afliftance of the micipfcope, yet 
with refped to their generic characters, bear the molt 
{hiking refemblance to the gigantic fpecies juft defcri- 
bed. Thefe minute Monoculi are very common ani¬ 
malcules, and may be, found in the fumm?r months in 
almoft all ftagnnnt waters. Some of them are figured, 
(though not very elegantly, vet with fufficient exact- 
nefs,) in Baker’s works on the miorofcope, and may. 
ferve as curious examples of the wonderful difparity of 
fize which fometimes takes place in animals of the fame 
genus. 
To what has been faid of the Monoculus Polyphe¬ 
mus, I fhould not omit to add, that the eyes in this 
animal, according to the obfervations of Mr. Andre, 
(Phil. Tranf. vol. 7a.) conffft of a great number of 
very fmall cones, in which refpect they differ from thofe, 
of mod other in feds, in which the outward coat of the 
eye i§ compofed of innumerable flight convexities, each, 
bounded by an hexagonal outline. It may be proper 
to add, that the eyes of moft of the fmaller fpecies o£ 
Monoculi 
