Further Notes on Dyscritina 387 
characters may perhaps be selected as distinctive of the 
genus Dyscritina. 
Larva with many-jointed caudal appendages. 
Adult with single jointed appendages in the form of 
forceps. Wings as in Forficula. Feet with pulvillus 
between claws. Number of antennal joints variable 
(normally 16 2). 
A glandular pore on each antennal joint in all stages of 
the insect. 
ON THE SPECIES OF DYSCRITINA REARED 
BY MR. GREEN. 
By Matcotm Burr, F.ZS., F.ES. 
THE great interest and importance of Mr. E. E. Green’s 
paper is twofold. First, it settles definitely the vexed 
question of the affinities of Dyscritina longisetosa, Westw., 
and to a great extent elucidates the economy of earwigs, 
about which little has been known, especially with regard 
to tropical species. Secondly, the facts disclosed 
throw much light on a more general question, the origin 
of the Forficulide and their phylogenetic relationship to 
other insects, particularly among the Orthoptera. 
An examination of the imagos which Mr. Green has 
bred from the Dyscritina form at once shows that they 
are to be referred to the genus Diplatys, Serv., to which 
Cylindrogaster, Stal, is nearly allied. 
These two genera are separated by Kirby in his 
synoptical table by the presence on the third and fourth 
abdominal segments in Diplatys of pliciform tubercles, 
which are absent from Cylindrogaster. Both genera are 
represented in the tropical part of the New World as well 
as in Africa and Asia. 
The surprising point shown by Mr. Green’s investigations 
lies not so much in fact that the mysterious larva has 
developed into an earwig, for that was to a certain extent 
foretold by most entomologists who examined the immature 
specimens, but rather in the manner in which the caudal 
setze develop into forceps. 
That the forceps of earwigs are the homologues of the 
cerci of true Orthoptera is now obvious, but their manner 
of development, in the species before us at least, is 
