34 TBANSACTIONS LIVEEPOOL BIOLOGICAL SOCIETY. 



have been described from our former laboratory at Puffin 

 Island. There are two cases — (1) that of Lamellaria 

 perspicua, and (2) that of Virbius varians — which we have 

 had under observation during the summer at the Port Erin 

 laboratory, and which may be of some interest to readers. 



(1) The following note on the "mimicry " of Lamellaria 

 appeared in the " Conchologist " for June 24th : — 



" About twenty years ago Giard pointed out that the 

 mollusc Lamellaria perspicua may be found associated 

 with various compound Ascidians, and is then protectively 

 coloured so as to form an excellent example of what he at 

 that time called direct defensive mimicry. 



" Lamellaria perspicua is not uncommon round the 

 south end of the Isle of Man, and is frequently found under 

 the circumstances described by Giard ; but I met lately 

 with such a marked case on the shore near the Biological 

 Station at Port Erin, that it seems worthy of being placed 

 on record. The mollusc was on a colony of Leptoclinum 

 macula-turn, in which it had eaten a large hole. It lay in 

 this cavity so as to be flush with the general surface ; and 

 its dorsal integument was not only whitish with small 

 darker marks which exactly reproduced the appearance 

 of the Leptoclinum surface with the ascidiozooids scattered 

 over it, but there were also two larger elliptical clear 

 marks which looked like the large common cloacal apertures 

 of the Ascidian colony. I did not notice the Lamellaria 

 until I had accidentally partly dislodged it in detaching 

 the Leptoclinum from a stone. I then pointed it out to 

 a couple of naturalists who were with me, and we were 

 all much struck with the difficulty in detecting it when in 

 situ on the Ascidian. 



" This is clearly a good case of protective colouring. 

 Presumably the Lamellaria escapes the observation of 

 its enemies through being mistaken for a part of the 



