158 THE ZOOLOGIST. 



Notes on London Lepidoptera. — In my note on a Butterfly abroad 

 in dull weather in the 'Zoologist' for last month (p, 114) the epithets 

 " large white " should have had capitals, for the insect was un- 

 doubtedly the familiar Pieris brassicce. I have seen P. rapa, an even 

 commoner insect, abroad under similar conditions ; but in this case 

 the specimen was evidently looking for shelter. I was once surprised 

 at finding a fine specimen of the Small Copper on a hoarding in Great 

 Portland Street, the only occasion on which I have seen this species 

 in London. But more remarkable was the occurrence of a specimen 

 of the Convolvulus Hawk-Moth on a balcony of the house formerly in 

 the occupation of the Zoological Society in Hanover Square, some 

 time in 1903 or soon after. This I boxed, and took up to Primrose 

 Hill, and released it there that evening on going home. — F. Finn. 



CRUSTACEA. 

 Hermit- Crab Capriciously Changing Shell. — What are the con- 

 ditions, apart from growth, which lead the Common Hermit-Crab 

 {Eupagurus bernhardtis) to change its shell ? Some individuals 

 appear to change capriciously. For example, one captive specimen, 

 of rather less than average size, removed from a "Whelk shell (which 

 bore a " Parasitic " Sea- Anemone) to another Whelk shell of about 

 the same size ; and in this house it remained for several days. It 

 then returned to the first shell. A few days later it removed to 

 a third Whelk shell. After remaining here for two or three days, it 

 migrated to the first shell, on which the Sea-Anemone still stood. 

 Neither of the two other shells bore Sea-Anemones, and all three 

 were clean, and of about the same size. This behaviour is occasion- 

 ally, but by no means commonly, to be observed in other individuals 

 of the Hermit-Crab. It seems to have no connection with the 

 presence or absence of a Sea- Anemone ; and it is difficult to ^decide 

 whether it has any connection with the presence or absence of the 

 v/orm Nereis fiicata. — H. N. Milligan. 



ECHINOIDEA. 

 Cannibalism in a Sea -Urchin. — In a recent paper in the' 

 ' Zoologist ' (pp. 81-99) on the feeding habits of the Purple-tipped 

 Sea-Urchin I pointed out (p. 89) that it was probable that a Sea- 

 Urchin ate the spines which fell from other Sea-Urchins, but that a 

 specimen had not yet been detected in the act of eating a spine. The 

 paper had been in print a week when I observed that a large Purple- 

 tipped Sea-Urchin, 42 mm. in diameter (excluding the spines), had 



