E P H 
E P H 
dccafions an almofl intolerable pain for a confider- 
able time; and afterwards fuperinduces fuch a pro- 
found fleep, that nothing, it is fiid, can awake the 
patient but the crulhing one of thofe creatures on 
the part affefted : it is, however, afferted, that flieep 
feed on thefe iniecfts without receiving the fmalleft 
injury. 
EPERLAMUS. A name fometimes given to 
the fmelt on account of it's pearly colour. 
EPERVIERS. The French appellation for 
that clafs of butterflies which conftitutes the fixth 
in Reaumur's diftribution. Thcfe infefts are di- 
ftinguiflied by their poifing themfelves on their 
wings after the manner of kites and other birds of 
prey, and never fettling on thofe flowers from 
whence they derive their fubfiftence, but fluttering 
with a humming noife while they thrufl: their 
trunks into the the cups of the flowers, and extra6t 
their juices. 
EPHEMERA. A diftinft genus of the order 
of neuroptera in the fyfliem of LinnJEus, diftin- 
guilhed by two gibbous protuberances above the 
eyes, ereft wings, and a briftly tail. This cele- 
brated naturalift: enumerates eleven fpecies of this 
clafs, difcriminated by their different colours, and 
the number of hairs in their tails, fome having 
two, and others three. 
The Ephem.era, or Day-fly, as it's name imports, 
though among the mofc minute of that kind of in- 
fefts, may be confidered as one of the moH curious 
obje6ls in natural hifl:ory. All the various fpecies 
are produced from eggs, in the form of worms; 
from whence they change to their aurelia fl:ate; 
and then adopt their lall mutation, viz. into beau- 
tiful flies, of longer or fliorter duration, according 
to their kinds. 
The Ephemera, in it's fly flate, is a very elegant 
winged infe6l, fl:rongly refembling the butterfly 
both in it's fize and fhape; but it's wings are not 
covered with that kind of painted duft with which 
thofe of butterflies in general are adorned and ren- 
dered opake. The Day-fly has four wings, the 
uppermofl: being conflderably the largefl:; and, 
when the creature is at refl:, it generally lays it's 
wings over each other on it's back. The body 
is long, and compofed of fix rings which are larger 
at their beginnin9:s than near their extremities: 
and from thence a tail proceeds longer than all the 
reft of the fly, confifting fometimes of three threads 
of unequal lengths, and at others of two long and 
one fliort. Before this beautiful form is acquired, 
the infeft mufl: have undergone all the various 
tranfmutations of it's kind : but it's glory is ex- 
ceedingly tranfient, for the hour of it's greateft 
perfeftion is that of it's death ; and it feems fcarcely 
introduced to pleafure when deftined to refign it's 
life. 
The reptile that is to become a fly, and which 
is granted fo long a term when compared to it's lat- 
ter duration, is an inhabitant of the water, and in 
many particulars bears a ftrong refemblance to 
fifties. It is furniflied with gills, by means of which 
it refpires at the bottom ; and pofleflTes alfo the ta- 
pering fliape of aquatic animals. It has, befides, 
fix fcaly legs, which are affixed to their corfelet; 
the head is triangular; the eyes, which are placed 
forwards, may be diftinguiftied both by their large- 
nefs and colour; and the mouth is furniflied with 
teeth. 
As there are feveral fpecies of Ephemera, their 
aurelia are confequently of different hues, fome 
being yellow, fome brown^, and others cream-co- 
loured. Some of them likewlfe excavate cells at 
the bottom of the water, from which they never 
ftir, but feed on the mud which compofes the walls 
of their habitations in con.tented captivity : others, 
on the contrary, range about, dive from the fur- 
face to the bottom, fwim between two waters, quit 
tliat element entirely in order to feed on plants by 
the river fide, and then return to their native 
abodes for protection and fecurity. 
But though the reptile exifts two, and fometimes 
three years, througliout all that long duration it of- 
fers but little to excite curiofity : it's moft ftriking 
peculiarities command our attention during the 
fliort interval of it's fly ftate, into which are crouded 
the moft important tranfaftions of it's life. The pe- 
culiar fign by which we may difcover that this rep- 
tile will fliortly change to a fly, confifts in a pro- 
tuberance of the wings on the back; about that 
time the fmooth and depreflfed form of die fuperior 
part of the body is cliangcd into a more fwolltn and 
round figure, fo that the wings in fome meafure be- 
come perceptible through the external covering. 
As but a very few fpecies of thefe infefts are na- 
tives of England, the curiofity of the naturalift cars 
only be fufficiently indulged by walking, about fun- 
fet, along the banks of the Rhine, the Seine, or 
fome other continental rivers in temperate cli- 
mates; where, for the fpace of about three days 
during the middle of fummer, their numbers and 
afliduity are perfe(ftly aftonifliing: thethickeft de- 
fcent of the flakes of fnow in winter feems hardiv 
to equal their numbers; the whole air appears as if 
animated by the new-born race; and the earth it- 
felf is almoft entirely covered with their remains. 
The aureliae, or reptile infefls, as yet beneath the 
furface of the water, wait only the approach of the 
evening, in order to commence their transforma- 
tion; the more induftrious diveft themfelves of 
their exuviae about eight o'clock, and the moft 
tardy are transformed before nine. Nothing, in- 
deed, feems to be cffefted with more facility than 
this laft metamorphofis ; the aurelijE are no fooner 
railed above the iurface of the water, than their 
old flieathing-ftcins burft; from the cavities of 
wljich flies iffue, wliofe wings inftantly unfolding, 
bear them, into the air. Millions of aurclise afcend 
in this manner to the top; and, inftantly becom- 
ing flies, fill all the vicinity with their flutterings. 
But thefe fportings are fpeedily terminated; for 
the whole fwarm, in the fpace of two or three 
hours, falling to the ground, covers the earth, after 
the manner of deep fnow, for feveral hundred yards 
on each fide of the river. 
Tiie males andfemales,'during their very limited 
exiftence, are differently employed. The former, 
quite inaftive, and apparently without defires, 
feem only born to die : unlike the males of other 
infefls, they neither purfae the females, nor fliew 
any averfion to themi; and, after fluttering for 
an hour or two, drop'down dead. But, v/ith re- 
ipe6t to the latter, the cafe is very diflerent; for 
fcarcely have they left the far face of the water, and 
dried their wings, when they haften to drop their 
eggs back again ; and thefe they depofit according 
to tlieir different fituations, fom.etimes on the wa- 
ter, and at others on the land. 
But as this account may perhaps be unfatisfac- 
tory to the inquifitive naturalift, who v/ill probably 
enquire by what means thefe eggs are fecundated, 
as no copulation whatever appears to take place be- 
tween the fexes during their tranfitory excurfions in 
air; we fliall anfwer his reafonabie enquiry by fir ft 
laving: 
1 
