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average breadth of 3 or 4 inches; 34 feet were of uniform diameter, and 19 
feet gradually tapered off towards the tail. This is all the more surprising 
as the Host-Worm had been discovered already a fortnight previously, and 
the many observers and lookers-on had carried off not inconsiderable 
numbers of larvae. 
On the 17th August, 1867, in the forenoon, the sky being cloudy and 
rain having fallen heavily on the previous day and gently on that morning, 46 
Host-Worm processions were noticed upon the wet leaves of a close beech 
forest not far from Hahausen on the Hartz ; they were from one to ten 
feet long, most of them about a hand's breadth in front and tapering 
gradually towards the end. The area on which this number was discovered 
was but 100 paces square, and the processions themselves were directed to 
nearly all points of the compass. The average length of these 46 trains 
was at least 5 feet, and their breadth 1 inch; and as on an average every 
square inch was occupied by about 200 of these travelling larva?, the total 
number of individuals in these 46 trains was above 552,000. If united, 
they would have formed a line 230 feet long and 1 inch broad or nearly 
60 feet long and of a hand's breadth. 
In Germany the Host- Worm has specially been noticed in the 
Thuringian Forest and on the Hartz, far more rarely in the plain and 
almost without exception in beech and oak forests. In consequence of the 
great attention which its appearance always attracted, the years in which 
it showed itself have in the science of natural history a more than usual 
interest and therefore deserve mentioning as far as they have become 
known. 
In the Thuringian Forest it was observed 17 times between 1698 
and 1867, for the most part near Eisenach. In the Hartz mountains 
21 times in the interval between 1804 and 1871; also near Tilsit in 
1845 and 1856; near Hanover in 1853; not far from Hernhut (Saxony) 
in 1853 and 1854; at Sarquidlen near Eastenburg in 1854; near Buchholz 
(Saxon Erz-gebirge) in 1860; near Attenbury in 1864; beyond Germany 
it has been found in Sweden, Norway, Lithuania, Switzerland (1851) and 
as already noticed in the Tatra and Karpathian mountains. 
