The Bionomics of the Tiger-beetle. 3 
feeding, and their favourite prey seemed to be blow-flies. A big blue-bottle 
might often be seen caught by the head and sticking out of a larval burrow. 
In this position its soft internal tissues would be extracted, and next day the 
empty integument might be found cast away at some distance from the hole. 
LARVZ KEPT IN CAPTIVITY. 
Sixteen large burrows having been marked to facilitate observation on a 
later occasion, sods containing eight others were dug up and taken to 
Edinburgh at the end of July 1913. Soon afterwards the inhabitant of one 
of these closed its hole by plugging the entrance with earth. A second larva 
closed its burrow on 25th August, another on 31st August, and a fourth on 
1st September, and by 7th September all the burrows brought to Edinburgh 
had been closed. At the time it was conjectured from the size of the larvie 
that the burrows were closed for pupation, but this surmise afterwards proved 
to be wrong. The larve were preparing for hibernation. The sods containing 
the burrows were kept in ordinary flower-pots placed at the base of a wall 
with a southern exposure, where they were subjected to the usual rigours of 
winter. From September 1913 till April 1914 the larvee remained hibernat- 
ing in their closed burrows. On 19th April 1914, it was noticed that all the 
burrows save one had been re-opened. Next day this last one opened, and all 
the larvee were given a meal of raw meat. On the following day, 21st April 
1914, one of them closed its burrow again. This time the retirement was for 
pupation, and before 8th May all the burrows under observation in Edinburgh 
had been re-closed. 
On 17th May 1914, the burrow which had been closed on 21st April 1914 
was examined by carefully splitting the sod. The larva was at the bottom of 
its hole and had not yet pupated. The two halves of the sod were joined 
together with as little dislocation as possible, and the sod was left undisturbed 
until 28th July 1914, when it was again opened up, and the adult beetle was 
found in the burrow. This beetle was transferred to a breeding-cage, and 
though torpid at first soon became quite active. On the following day 
(29th July 1914) two other burrows, which had been closed at the end of 
April 1914, were examined and found to contain pup. It was possible 
to preserve one of these burrows without its walls crumbling away, yet 
admitting a view of the pupa within. On 9th August this pupa had changed 
to an imago, but it was still quite white and remained in the burrow. Next 
day its thorax had become green. On the third day the beetle was coloured 
all over, though with a bluer tinge than maturer insects exhibit. In this 
state it was placed with the other beetle, which, instantly recognising its soft 
