150 PORTLAND LEPIDOPTERA. 



There are a few species to which I wish to allude, mostly repre- 

 sented in my list by only one or two specimens, whose food-plant 

 does not, so far as I know, occur at Portland (though it may do so 

 singly in gardens or other cultivated ground), or which are usually 

 found under very different circumstances. Firstly, there are three 

 moths which are as a rule only found on heaths, Selidosema 

 ericetaria, Agrotis strigula, and Phycis fusca, the latter moth having 

 a special partiality for burnt places on heaths, in which, being black 

 it is well concealed, or possibly as Mr. C. J. Barrett (in Entomolo- 

 gical Monthly Magazine, xxiii., 108) doubts if any sufficient 

 advantage would accrue to it from concealment to cause such a 

 permanent habit through natural selection, it may be that it is 

 merely a lover of heat, and finding the black parts of the heath 

 warmer than the rest, it stays on them when once it reaches them. 

 The food-plant is, I believe, not known, that of Agrotis strigula 

 is heath only, whilst S. ericetaria eats heath or bird's-foot trefoil. 

 There are also several oak species, and oak is either absent or very 

 scarce. Mr. Dale tells me he knows of none at Portland. Crypto- 

 blabes bistriga, which is recorded by the Rev. 0. P. Cambridge, is 

 an oak species, and so is Lithocolletis messaniella, which, however, 

 also feeds on evergreen oak. 



Dioryctria splendidella feeds on fir, which I have not seen at 

 Portland, and Triphosa dubitata on buckthorn (Rhamnus cathar- 

 ticus) which I feel almost sure does not occur there. This last 

 species is however of regular occurrence, and doubtless feeds on 

 some other plant perhaps blackthorn. 



The many difficulties in the way of collecting at Portland, 

 including the proverbial bad entomological weather which prevails 

 there and the rough nature of the ground, perhaps account for the 

 fact that many of the species of my list have only been taken by 

 one or two collectors. This fact also makes me hope that many 

 additions may be made to this list at no distant date and that new 

 species yet lurk concealed there which will still further increase 

 the fame of Portland as a first-rate entomological collecting 

 ground. 



