MARINE BIOLOGICAL STATION AT PORT ERIN. 35 



Leptoclinum colony ; and the Leptoclinum being crowded 

 like a sponge with minute sharp-pointed spicules is, I sup- 

 pose, avoided as inedible (if not actually noxious through 

 some peculiar smell or taste) by carnivorous animals 

 which might devour such things as the soft unprotected 

 mollusc. But the presence of the spicules evidently does 

 not protect the Leptoclinum from Lamellaria, so that we 

 have, if the above interpretation is correct, the curious 

 result that the Lamellaria profits by a protective charac- 

 teristic of the Leptoclinum for which it has itself no 

 respect, or to put it another way, the Leptoclinum is pro- 

 tected against enemies to some extent for the benefit of 

 the Lamellaria which preys upon its vitals. 



W. A. Herd man." 

 (2) It will be remembered that the colour variations of the 

 small prawn Virbius varians whereby individuals resemble 

 the green, the red, or the brown seaweeds they are asso- 

 ciated with, or even sandy and gravel bottoms, were 

 discussed and illustrated by a coloured plate in last year's 

 report, and the question was raised as to whether, or to 

 what extent, the adult animal could change its colour. 

 We have had a number of specimens, of various colours, 

 under observation in the laboratory during the year, and 

 they have been kept in jars with various colours of seaweed 

 and of background, and in very different amounts of light. 

 These experiments have shown clearly that the adult animal 

 can change its colouring very thoroughly, although not in 

 a very short space of time. To take an example or two 

 from my notes : — 



I. One speckled-red and two brown specimens were put 

 in a glass jar containing bright green sea-weeds (Ufoaand 

 Enteromorpha) , on a sheet of white paper, in direct sun- 

 light, on September 6th, at 9 a.m. At 8 p.m. all the 

 brown and red colour had gone, the three specimens were 

 all of a pale amber tint, and " washed-out " looking. 



