NOTES AND QUERIES. 313 



range of this species from the Mediterranean, I have no doubt that it will 

 soon become as common in the English Channel as it now is in the 

 Mediterranean, for it is a curious fact that British specimens are finer than 

 those from the Italian shores. It is also a species that should increase and 

 multiply, for not only is it frequently covered with sponge-growth, thus 

 protecting it from the attacks of fishes to whom crustaceans are food but 

 sponges are not, but the animal itself closely resembles, when at rest, an 

 Echinoderm, Amphidotus cordatits, the fine grey bristles or spines of which 

 are equalled in appearance by the grey pile of Dromia vulgaris, whose legs, 

 too, are capable of being packed away closely out of sight, thus completing 

 the illusion (to its fish-enemy), for I believe Echinoderms are not sought 

 after as food by fish. I could refer to other crustaceans and echinoderms 

 which I believe are finding their way northwards from the Mediterranean, 

 but I have already overstepped my limit for a note. I should like to see 

 in 'The Zoologist' more records of rare crustaceans. — Edward Lovett 

 (West Burton House, Croydon). 



INSECTS. 



Butterflies mobbing Small Birds.— While staying in Sweden, iu 1883, 

 I noticed a remarkable habit on the part of the Grayling butterfly, Satyrus 

 semele. This was on an island a few miles north of Goteborg, which was 

 mostly low-lying rock. Small birds, Pipits or Wagtails, flying over these 

 rocks were frequently pursued for a short distance by these butterflies, 

 which would sometimes start up from the rocks and dash off after the 

 bird, and regularly mob it, as small birds will a hawk, sometimes even flying 

 up to the bird ten or fifteen feet in the air. When I first noticed this 

 I thought the bird was trying to take the butterfly, but on subsequent 

 occasions I saw clearly that the butterflies were the aggressors. At times 

 a single butterfly would go to the attack ; at other times three or four 

 would start off together. I should much like to know whether similar 

 occurrences have been noticed. The Grayling butterfly struck me as being 

 a most beautiful example of assimilation of colour to surrounding objects ; 

 indeed it goes, further than trusting merely to its colour for protection ; for 

 not only does it close its wings immediately on settling, and thus, with 

 its delicately pencilled under surface of grey and brown, become almost 

 identical with the lichen-powdered grey rocks, but it rests at a very acute 

 angle to the surface of the rock, so that it casts scarcely any shadow from 

 the sun, and when seen in profile, is scarcely in relief from the surface of 

 the rock on which it rests. Surely it would be a sharp-eyed bird which 

 would find this butterfly at rest, and a clever one to take it on the wing.— 

 George E. Lodge (5, Verulam Buildings, Gray's Inn). 



ZOOLOGIST.— AUGUST, 1888. 2 B 



