SUGGESTIONS AS TO THE MEANING OF THE SHAPES 
AND COLOURS OF THE MEMBRACID^E, IN THE 
STRUGGLE FOR EXISTENCE 
By EDWARD B. POULTON 
D.Sc., M.A., Hon. LL.D. (Princeton), F.R.S., &c. 
HOPE PROFESSOR OF ZOOLOGY IN THE UNIVERSITY OF OXFORD; FELLOW OF JESUS COLLEGE, OXFORD; 
PRESIDENT OF THE ENTOMOLOGICAL SOCIETY OF LONDON 
In studying the meaning and use of insect colour and form it is deeply interesting 
to compare broadly the two great divisions of the Rhynchota. The Heteroptera 
(Hemiptera) are obviously, as a whole, a specially protected group, commonly 
defended by taste or smell from large numbers of insect-eating animals. Warning 
or aposematic colours and patterns abound among them, while their movements are 
such as to promote the conspicuous effect of strongly contrasted tints. Groups of 
species in the same locality often possess similar aposematic colours, thus enabling 
their young and inexperienced enemies to learn and remember the appearance of 
unpalatable forms, with a comparatively small waste of life. Such resemblances are 
often spoken of as Mullerian Mimicry, after the naturalist who first suggested the 
benefits which arise from facilitating the education of foes. They may also be 
called by the more descriptive title “Common Warning,” or “Synaposematic ” 
colours. For it is clear that in such cases we have to do with the useful possession 
of warning colours in common rather than with the benefits conferred by “ Protective 
Mimicry ” (Pseudaposematic colours) as defined by H. W. Bates. By these latter 
resemblances a rare, much persecuted, palatable form is believed to be mistaken by 
enemies for an abundant species, well known and avoided because of some special 
mode of defence. Good examples of S. African Heteroptera with common 
warning colours have recently been described and figured by Mr. Guy A. K. Marshall 
[Trans. Ent. Soc. Lond ., 1902, p. 537). 
When we find the Heteroptera resembling specially protected insects of other 
Orders, such as the conspicuous distasteful groups of Coleoptera : the Lycida (l.c. 
p. 515), the Cantharida (p. 518), the Coccincllulce (p. 520), or the aggressive 
