180 
Observations on the various Insects 
trica, often accompanies the Polydesmus, and assists in such 
depredations. 
The Otter Caterpillar. 
On cutting throuo;h a carrot in January last, which was black 
and decayed inside, I was very much suprised to find a cavity 2 or 
3 inches long, and within a large white caterpillar, which unfor- 
tunately was so injured by the knife that it died. It was, how- 
ever, unquestionably the larva of a Ghost- Moth, named Hepialus 
liiLmili.* It was evidently preparing to change to a pupa, for 
it had cast its skin, which was pushed to the bottom of the cell, 
and a loose web was spun across the top. This fact shows that 
the Otter Caterpillar will feed upon roots very different in their 
nature from those of the hop. I must pass over the economy of 
this destructive insect for the present, as its history is more im- 
mediately connected with the Hop-gardens. 
We will novv leave the roots of the carrot, and proceed to in- 
vestigate the injuries sustained by the foliage, flowers, and seeds, 
as they arc successively developed. 
Paph.io Machaon, the Swallow-tailed Butterfly. 
This is the first to be noticed ; but it is an insect so far from 
common, being entirely confined to certain localities in this 
country, that it is rather with a view of completing the history of 
the Carrot insects, than from any necessity of guarding the agri- 
culturist against its inroads, that it is introduced. It is, however, 
abundant in France, where the graceful evolutions of the Swallow- 
tailed Butterflies may sometimes be seen even in the gardens of 
towns. As England is being better drained, many native insects 
are expelled from their ancient haunts, and are becoming extinct 
in some districts : this is the case with Papilio Machaon, whose 
geographical range has been greatly circumscribed by cultivation 
within a comparatively short period. Some forty years back this 
conspicuous butterfly appeared annually in neighbourhoods 
where now it is never seen. My friend Mr. Dale, of Glanville's 
Wootton, used to observe it annually sailing around his property 
in Dorsetshire, where now it may be searched for in vain, al- 
though the same hills, pastures, and plantations remain pretty 
nearly as they were at the time alluded to: it was also formerly 
abundant at Westerham, in Kent, and around London ; but at 
present, if any one wishes to find this beautiful butterfly he must 
go to the fens of Cambridgeshire, Huntingdonshire, or Norfolk, 
where, at Burwell, Whiltlesca, and Horning, 30 or 40 may be 
taken in a fine day from May to midsummer. 
* Curtis's ' Brit. Ent.,' fol. 185. « Guide,^ Genus 791, No. 1. 
