Phenomena of Autotomy,. 473 
ever upon which to base such a decision, and therefore, in 
spite of its affinity to the Angolan race of 7’. evippe, I am 
constrained to consider it a distinct species. 
The argument on which Mr. Marshall bases his synonymy 
of 7’. evippe and T'. omphale, which he regards as one variable 
species, is based upon the confusion which existed previous 
to its rearrangement in the drawers of those species in the 
Museum collection—a confusion largely due to the incorpora- 
tion of accessions since the date of the first arrangement of 
the genus about the year 1876 or 1877. He says that in 
Eastern Africa 7’, evippe is ‘an intermediate seasonal form 
of theogone-omphale”’ ; but this is certainly not the case, for 
T. evippe is essentially, in all its characters, a wet-season 
phase; nor does it appear to extend in the Hast further north 
than Natal. 
[To be continued. } 
LIV.—Phenomena of Autotomy observed in the Nymphs of 
Monandroptera inuncans, Serv., and Rhaphiderus scabrosus, 
Serv. By Epmonp BorpDAGeE*. 
In the month of September last year I succeeded in obtaining 
larve and nymphs of Monandroptera tnuncans and Rhaphi- 
derus scabrosus, in which I studied the phenomena of autotomy, 
in order to compare them with those that [ had observed in 
the case of the adult insects. 
These phenomena were exhibited very clearly by the very 
young larve. On pinching hard the distal extremity of the 
femur, I generally produced the separation of the limb. The 
interval that elapses between the stimulation of the nerve and 
the rupture of the limb varies from a few tenths of a second 
to three or four seconds. ‘lhe same operation could be 
attempted successfully upon all six limbs. 
In the case of the older larvae and nymphs autotomy is 
sometimes produced still more easily ; but it may happen 
that it becomes irregular and capricious—a feature that we 
have already pointed out in the adult Phasmids. We must 
also make mention of the increase in the time between the 
stimulus and the rupture. Although this increase is not 
manifested in an absolutely universal manner, it is of very 
* From the ‘Comptes Rendus, t. exxiv. no. 4 (Jan. 25, 1897), pp. 210— 
212: trom a separate impression communicated by the Author. 
dnn. & Mag. N. Hist. Ser. 6. Vol. xx. 32 
