474 M. Edmond Bordage on Autotomy in 
frequent occurrence and may be expressed by a certain 
number of minutes. 
It has happened that I have pinched, till I crushed them 
between the finger-nails, several limbs of a nymph, without 
succeeding in producing autotomy. 
Quite tired out, I placed the insect upon a table: it moved 
along with difficulty, dragging its legs, which had been 
rendered useless ; then, after four or five minutes (a quarter 
of an hour sometimes), the injured appendages broke off 
cleanly, not at the points where they were crushed, but always 
at the spot at which rupture by autotomy normally takes 
place. Only in a few cases have I seen the crushed limb not 
separate itself from the thorax. Judging by their lack of 
vigour and by a certain flaccidity of body, I am led to believe 
that I was then dealing with nymphs on the point of per- 
forming an ecdysis. Moreover, the experiments attempted 
upon them were followed shortly by the death of these insects. 
_ The influence of thermic agents seldom gave me good 
results. A limb which I placed in contact with a lighted 
match sometimes detached itself after a few seconds; in other 
cases it allowed itself to be charred until reduced to a mere 
stump without becoming detached from the thorax. 
The rapid section of the femur, at whatever point it be 
performed, does not always produce autotomy (nevertheless 
this process infallibly occasions the rupture of the great limbs 
of the grasshopper). Sometimes, after having thus ampu- 
tated part of the limb in vain, I placed a lighted match in 
contact with the wound, and it was only in certain cases that 
this produced the spontaneous severance of the stump. ; 
Since the effect of the bites of ants is identical with what 
we observed in the case of the adult insects, we will not 
revert to this point. We may mention, however, that we 
have never seen the ants succeed in producing the autotomy 
of all six limbs. 
As we have already stated, the phenomena of autotomy 
are not exhibited in a regular manner in the Phasmidea, at 
least in the species that we have studied. In spite of this 
our experiments, performed upon a large number of specimens 
of Monandroptera and Lhaphiderus, have enabled us to 
establish the fact that in the nymphs autotomy becomes in- 
creasingly difficult in proportion as these nymphs draw nearer 
to the final metamorphosis. 
Since the month of September 1896 I have kept in cap- 
tivity nymphs of Rhaphiderus and Monandroptera, a thing 
somewhat difficult to do, since these insects normally live at 
an altitude of upwards of 700 or 800 metres. They browse 
