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arc going over the winter. Aberrations from Navestock, Essex.— Mr. 
Tutt, on behalf of the Rev. W. Claxton : Anchocclis pistacina ab. 
serina, and ab. venosa ; Ayrotis exclamationis ab. picea ; Xylophasia 
hepatica ab. charactered ; Miselia oxyacanthae ab. capucina. Aberra¬ 
tion of Arctia caia.— Mr. Clark : A curiously suffused aberration of 
Arctia caia, bred from a larva captured at Walthamstow. The 
Microscope.— Mr. Nicholson read a paper on “ The Microscope,” for 
which a hearty vote of thanks was accorded him. 
Nov. lGth, 1897.- — Larv.e of Lasiocampids. — Mr. Bacot exhibited 
living larvai of S. French Lasiocampa quercus, S. French L. spartii, L. 
callunae from Aberdeen, cross between 3 English and 2 French quercus, 
cross between 3 L. spartii and $ L. callunae, cross between 3 
French L. quercus and 2 L. callunae. He also exhibited preserved 
larva; of L. ruhi, L. quercus from the S. of England, L. trifolii, cross 
between 3 L. spartii and 2 English L. quercus, cross between 3 
French L. querciis and 2 L. callunae, S. French L. quercus. Mr. 
Bacot read the following notes on his exhibits “ I exhibit to-night 
larva; of L. quercus, with its different varieties or sub-species cal¬ 
lunae, spartii, and French querciis, together with larvae of crosses 
between those different races. I will briefly call attention to the 
principal differences between the adult larvae of the several stocks, 
and afterwards of the crosses. These differences consist chiefly in 
the colour of the hairs, and these may be, for convenience, divided 
into two classes : firstly, the long hairs more or less evenly distributed 
all over the body; and, secondly, the fine short hairs, closely massed 
together on the dorsal and sub-dorsal area (of the larvae) forming a 
thick fur, most probably of a protective nature, as these hairs are 
easily detached, and produce great irritation in the skin. In French 
quercus both kinds of hairs are pure white. This I take to be tbe 
most specialised form in one direction. With spartii the short fin¬ 
is bright red-brown, the long hairs being white. My sicula are, as 
yet, too small to be compared, but a larva Mr. Warburg showed me 
was very similar to spartii as regards colour, though possibly a little 
paler ; callunae has both long and short hairs of a dark brown, 
approaching the hairs of L. ruin in colour. This I take to be the most 
specialised form in the opposite direction to French L. quercus. I 
would call the members’ special attention to the difference between 
callunae and English quercus, which, in the southern counties at any 
rate, has the short fur of dirty white, or dusky colour, with the long 
hairs brown. No doubt a perfect series of transitional forms, from 
French quercus to callunae, might be obtained, but there seems no 
doubt that the larvre of the races inhabiting the extremes of latitude 
are distinct. In their early stages, the two French forms are alike, 
but very different from the English races, querciis and callunae, which 
are also almost, if not exactly, similar in their early stages. The 
larva of sicula follows the other Continental races rather than the 
English form, but it differs in several points as to coloration and 
pattern. Now, as to the crosses, the larva of 3 spartii with 2 cal¬ 
lunae has the hairs of a rich red-brown, with a few scattered long 
white hairs. Spartii 3 with English quercus 2 is similar to above, 
but rather lighter coloured. French quercus 3 with callunae 2 
have the fur of a pale pinkish-brown, English quercus 3 with 
