MEMOIR OP THE LATE JOHN SCALES. 
Ill 
posseRS, a.s far as ray knowledge of them will permit. A moment’s reflection 
must convince us that it is impossible for them to arrive here with an easterly 
wind (alluding to the aphides)f rom two reasons, viz., on their first appearance 
here they are just excluded from the egg in an imperfect or larva state, and 
have no wings to enable them to fly, and those we generally observe are 
females, the males being very few in proportion, and are seldom found till 
Midsummer; and supposing they had wings, the myriads which attack our 
peas, during the season, would almost cloud the atmosphere, and strike our 
faces in their approach : but as their history, and most wonderful powers of 
fecundation, told us by Reaumur, may not be uninteresting to your readers, 
T sliall beg to insert it. lie informs us, “ That at one time they are oviparous, 
at another viviparous, and that the sexual intercourse of one original pair 
serves for all the generations which proceed from a female of a succeeding 
year, lie has also proved that one aphis may be the progenitor of 5,904,900,000 
descendants, and it is supposed that in one year there may be 20 generations.” 
If a young one bo taken immediately upon exclusion from the mother, and 
kept apart, it will produce }'oung, which young, if also kept apart, will 
likewise produce, and so on, without the presence of a male. About 
Midsummer, however, this singular fructification begins to lose its wonderful 
ellects ; the aphides cease to breed females only, males are likewise produced, 
which immediately celebrate the nuptial rite, and communicate fertility to 
the whole female posterity of a future summer. Can we wonder then at the 
rapid increa.so of them, which are daily observed on the peas during the 
summer in which they are affected ? 
The spotted appearance of the Gooseberries alluded to in the first part of 
this Letter, is caused by a parasitical plant called -Ecidium Grossularim, 
which like all other fungous parasites, when arrived at maturity, the pollen 
or dust observable in the shields, is wafted by the least breath of wind in 
ever}’ direction, and when it meets with a plant whose sap is favourable to its 
growth, it there fixes, and from a mere speck at first, increases and spreads 
rapidly, and when it has attained its perfection is again dLspersed upon its 
neighbours. There are probably many shrubs favorable to this parasite. 
Should I, by the above observations, be the instrumental cause of 
befriending those harmless creatures, the Lady Birds, and of rendering any 
information to your readers, I shall, with pleasure, subscribe myself. 
Your obedient Servant,' 
JOHN SCALES. 
Jieachamicell, near Swaff'ham, 
June 14/A, 1819. 
