g 
f. 
‘ 
Iife History of Tetropiwm gabrielt. 193 
Of the autumn broods, ova continued to hatch out till the third 
week in September.* 
I also obtained ova in November 1905 by artificial heat, from 
imagines of another second brood forced in their latter stages over a 
fire-place in a high temperature. 
In the latter case the beetles laid with great effort, dragging the 
extended ovipositor over the bark for days, but only laying a few 
eggs, though they lived their whole span of life. These ova did not 
hatch out. 
In breeding Zetropiwm a good way to obtain eggs is to 
enclose several laying 2? on not more than a foot of small 
larch wood enclosed loosely in muslin, On removing the 
lamin of bark with a penknife the ova will be found to 
occur frequently over this small area, and thus much time 
be saved in searching for them. 
To date ova, enclose 2? on a log for a day, removing 
them each day to another log, dating each log and enclosing 
it again in muslin to prevent any further oviposition from 
other quarters. 
Great care should be taken each day to remove all the 
2° that were put on the log. 
Though one may mark the spot where a @ is laying on a 
tree, on searching for the ova it is not easy to find them, 
so securely are they hidden away as a rule. 
They are not sealed over, as I have observed is the case, 
for instance, with Metecus paradoxus. 
The egg is 141-14 mm. long, elongate, subcylindrical, 
sometimes slightly broader at one end, milky white. 
Another good way of obtaining ova is to place the fertile 
? in a large glass jar with wide neck, covered with muslin 
or the metal top perforated, with a good-sized piece of 
bark in it and small chips at the bottom to ensure a 
foothold, placing the jar in the open air, though taking 
care not to allow the direct rays of the sun to fall on it 
during the hot hours of the day, nor the rain. 
Hatcuinc.—In a warm June or July temperature the ova hatch 
out in 14-16 days from the time of oviposition. From the eighth day, 
approximately, the larva may be seen slowly forming within the shell. 
Cloudy rings of the different segments appear ; a yellowish tinge at 
the larger end where the head is forming ; then ferruginous, passing 
to brown, specks for the mandibles, which, for a few days prior to 
pe ee ee eee 
* The perfect insects emerged the following July. 
