INSECTS INJURIOUS IN 1902. 55 
graph will illustrate the action of the oil, and the appearance of 
the water at -intervals of a few moments after application. 
Figs. 1, 2, 3, being taken within one minute of each other, and 
Fig. 4 a little later. 
A sample left with the Station Chemist was reported as be- 
ing a coal-tar creosote product, with a specific gravity of 1.03. 
The white “precipitate” observed when Phinotas is added to water 
(see photos), is the material separation of phenol derivatives. 
The use of oil of some sort in this connection is no new thing. 
Kerosene, it is reported, having been applied for this purpose as 
early as 1847, and some kind of oil unknown to the writer was 
suggested apparently as early as 1812. 
ROACHES, COCKROACHES, CROTON BUGS. 
Ectobia (Phyllodromia) germanica. 
This offensive household pest, almost worid-wide in its dis- 
tribution, so common in large cities, and known under the names 
given above, needs no special description. Families living in 
flats perhaps are greater sufferers than others, because no mat- 
Fig. 49.—Blatta germanica; (a) first stage; (b) second stage; (c) third stage; 
(d) fourth stage; (e) adult; (f) adult female with egg case; 
(g) egg case enlarged; (h) adult with wings spread. 
All natural size except g. From ‘‘House- 
hold Insects,”’ published by U. 8. 
States Div. of En- 
tomology. 
ter how energetic one occupant may be in his efforts to exter- 
minate the pest, if the other families in the flat make no attempts 
in this direction, the Roaches soon return to their old quarters. 
Many repellant poisons have been suggested, but this particular 
species seem very wary of poisoned baits. Undoubtedly the most 
