NOTES AND QUERIES. 79 



brownish colour, but on being brought to the fire it turned to a 

 bright yellowish-green with several light lilac patches on each side. 

 It may also be remarked that the side of the animal near the fire 

 turned of a light colour more rapidly than did the other side. The 

 general colour of the animal since its capture has varied from dark 

 green to light yellowish-green, and at no time have I seen it resume 

 the dark brown colour. — H. N. Milligan. 



CRUSTACEA. 

 Hermit-Crabs Changing Shell in Face of Danger. — In September 

 of 1915 I put several examples of the Common Hermit-Crab 

 (Eupagurus bernhardus) into an aquarium which already contained 

 two average-sized and pugnacious Shore-Crabs. Five Hermit-Crabs, 

 whose stained and battered shells were easily to be distinguished 

 from the clean whelk shells which were present in the aquarium for 

 the use of the newcomers, had been dropped into the tank, when the 

 Shore-Crabs proceeded to attack the Hermit-Crabs and to try to pull 

 them from their shells, in which efforts, however, they were not 

 successful. I had turned away, for only about a minute or a minute 

 and a half, in order to examine further into the contents of the 

 collecting-can in which the Hermit-Crabs had travelled, when my 

 attention was called by an attendant to the behaviour of the Hermit- 

 Crabs in the tank. Two of them had quickly changed into new 

 shells, and I was in time to see them retreating across the floor of 

 the tank in front of a demonstrative Shore-Crab. Perhaps the 

 Hermit-Crabs had been ready to change shells at the time they were 

 captured at the seaside ; they had been so much alarmed by the 

 attacks of the Shore-Crabs in the tank that they had preferred to 

 take the momentary danger of the change from shell to shell to with- 

 standing the attacks of their enemies. The difference in size between 

 the old and the new shells was by no means marked, and this raises 

 some perplexing questions, e. g., By ivhat means were the Hermit- 

 Crabs able to decide so rapidly that the new shells were to be preferred 

 to the old ones ? Hermit-Crabs are so commonly kept in aquaria 

 that observations should be fairly plentiful, and it would be of 

 interest to know what facts similar to those mentioned above have 

 been recorded in the note-books of those who keep marine aquaria. — 

 H. N. Milligan. 



ASTEROID E A. 



Cushion-Stars Attacking Brittlestars. — On the afternoon of 

 March 3rd, 1915, I obtained three individuals of the Common 



