The natatorii, thofe that ferve as oars for fwimming. The
thighs of the fa lta torii are remarkably large, by which means they
have confiderably more ftrength and power for leaping. The
feet o f the natatorii are flat, and edged with hairs; thus have a
proper furface to ftrike againft the water, as in the dytifcus,
notonefta, &c.
Such feet as have no claws are termed mutici. The chelae,
or claws, are an enlargement of the extremity o f the fore feet,
each o f which is furnifhed with two leffer claws, which a ft like a
thumb and finger, as in the crab.
The under part o f the feet, in fome infects, is covered with a
kind of brufh or fponge, by which they are enabled to walk with
eafe on the molt polilhed fubllances, and in fituations from which
it would feem that they mult neceffarily fall.
“ They tread the ceiling, an inverted floor,
And from it’s precipice depend fecure.”
Many infefts can only move the thigh in a vertical dire£tion;
while others can move it in various directions. The progreflive
motion o f infefls, and the various methods employed to effect it,
will be found a very curious and important fubjeft, and well
worthy the attention of the natural hiftorian. The mechanic will
not find it loft labour i f he bellows fome time on the fame feb-
jeft. Very little has been done on this head, and that principally
by Mr. de Reaumur, in his excellent Memoires; and by M.
Weifs, in a memoir publilhed in the Journal de Phyfique for
1771. The reader may alfo confult Borelh de Motu Animalium.
- Motion
Motion is one o f the principal phaenomena of nature, and as it
were the foul of our fyftem; and is as admirable in the fmalleft
animal as in the univerfe at large. It may not be amifs juft to
notice here, that there are fome infeas of the beetle kind, which
contradift an affertion o f Borelli’s, that an, animal puts in aftion
each foot on one fide before it moves thofe on the oppofite fide;
whereas thefe employ in walking the two moll diftant feet on the
fame fide, and the middle foot on the oppofite ; a method which
is firm and natural.
T he wings, thofe organs by which the infea is enabled to
f ly ; fome have only two, others are furnilhed with four, two on
each fide ; thefe are in fome of the fame fize, in others the fu-
perior ones are much larger than the inferior. The variety in the
form and ftruaure of the wings is almoft infinite; the beauty of
their colouring, the art with which they are conneaed to the
body, the curious manner in which fome are folded up, the fine
articulations provided for this purpole, by which they are ai
up in their cafes when out of ufe, and yet ready to be extended
in a moment for flight; together with the various ramifications,
by which the nourilhing juices are circulated, and the wing
{/lengthened, afford a fund of rational mveft,gallon highly entertaining,
exhibiting, particularly, when examined by the micro-
fcope, a moll wonderful difplay of divine wifdom and power.
The more delicate and tranfparent wmgs are covered an pro-
feted by e l y t r a , or cafes, which-are generally hard andopake
often highly polilhed, adorned with ornamental flutmgs, and
ftudded with brilliants. The wings of moths and butterfhes ar
mollly farinaceous, covered with a fine drift, that occafions thofe
beautiful colours with which they are fo elegantly P ^ t e d ^ o r