( exlviii ) 
moving) base further and further in that direction in which 
it was originally projected. Reflection will show how this 
movement was sure to end, and did end. The scalpellwm 
ultimately worked its way towards the insect’s belly till it 
had worked itself clear of the stem altogether, and left behind 
itself a more or less quadrant-shaped pouch or pocket, as deep 
as its own length and slightly longer at the mouth than it 
was deep. The sides of this pouch were scoured and torn, 
bleeding sap profusely, owing to the manglings which had 
created it—the wound, in fact, was such as would result from 
thrusting a spear-head into living flesh and tearing it out 
again, not perpendicularly but in a lateral direction. 
The nidus being now completed, the insect prepared for 
oviposition. The hunched abdomen straightened itself out 
again ; and the scalpellwm returned to its “ half-cock” position, 
just as it stood before the incision commenced. It then re- 
entered the stem precisely at the point where it had first 
entered it, and once more buried itself up to the hilt, on this 
oceasion naturally meeting no resistance worth mentioning, 
but still appearing to proceed with a certain amount of 
circumspection, and, as it were, to grope about with its tip, 
in search of the absolute bottom-corner of the pocket. This 
reached, a long greenish egg was extruded from near the 
base of the saw-sheath, entered the base of the scalpellum, 
and was gradually pushed or squeezed along its hollow 
interior, till it tumbled out from between the two “saws” 
not at but just before their apices, and so rolled into the 
bottom of the pocket. The sca/pellwm was immediately pulled 
straight upwards out of the pocket by the reascending tip of 
the abdomen, and the process was completed. 
I should have said that the passage of the egg into the 
interior of the ovipositor (= scalpellum) was accompanied by 
strange and quite indescribable agitations at the base of this 
organ—it seemed to wriggle and rock like a cork tossing among 
big waves. According to both Réaumur and Vallisnieri, not an 
egg alone, but a drop of some viscous venom is extruded from 
the abdomen, for the purpose, as they suppose, of preventing 
the wound in the plant from healing up again. This I can 
neither affirm nor deny from my own observations. The 
