Q [Januiiry, 



PROTECTIVE RESEMBLANCE OF PENTHINA GENTIANANA AND 

 EUPCECILIA ROSEANA. 



BY HERBERT FOBTESCUE FRYER. 



In the autumn of last year I collected a number of teasel heads, 

 seed heads of Dipsacus sylvesiris, containing larvae which Mr. Barrett 

 vaiovmedi me svQrQ t\xQ?,e oi Pentliina gentianana feeding on the pith 

 of the receptacle, and Eupoecilia roseana feeding on the seeds them- 

 selves. 



The heads were put in an outhouse for the winter, and watered 

 occasionally to prevent their becoming too dry. In due time the 

 imagines appeared. 



My motive in writing the present note is to call attention — pro- 

 bably unnecessary in the case of those who have bred them — to the 

 protective resemblance shown by both these species towards their 

 environment. 



The habit of P. gentianana on its emergence is to sit with head 

 buried between the spinous scales of the receptacle, and with the 

 posterior portion of its wings projecting a little beyond them. Roughly 

 divided (as the insect is into a light upper and a dark lower part) its 

 resemblance when in this position to a bird's excrement is very 

 noticeable. 



If a number of teasel heads be examined, it will be found that 

 in some instances the inner part of the seeds, i. e., that part which is 

 in contact with adjacent seeds, assumes a bright pink colour. Now, 

 £". roseana has a very frequent habit of sitting lengthways along the 

 spines of the scales above referred to, and here again, the resemblance 

 of the insect, with its colouring of rosy-pink shading into yellow, to 

 a partly displaced seed is worthy of notice. 



The larvae of the Torti'ices being concealed feeders, protective 

 resemblance is of use to them only in the perfect state, but in other 

 groups it is otherwise, and it would be an interesting work to take a 

 number of species and tabulate them, dividing them into three classes, 

 i. e., those which are protected in the first, in the first and second, and 

 in all three stages of existence. 



Classification by structural characters alone, and unless checked 

 by habit of life and method of development, may have the effect on 

 the Insecta that misfortune is said to have on the human race, " make 

 them acquainted with strange bedfellows." 



It is not impossible that facts elicited by this systematic study of 

 protective resembhince might be found to be of some assistance in the 

 determination of the phylogeny or relative age of a genus : for it 



