SLUGS AS MYCOPHAGISTS 225 



Limax maximus, like most other slugs, hides during the day in 

 crevices under stones or in the soil, and only emerges from its place 

 of retreat as darkness is coming on. It was therefore necessary 

 for me to make my experiments during the evening and night. 

 Slugs and snails possess to a considerable degree the power of 

 homing, i.e. of returning to the same hiding-place day after day, 

 after their night excursions in search of food. 1 My observations 

 have convinced me that Limax maximus is a homing slug. The 

 slugs used in my experiments had a fixed abode to which they always 

 returned after their nocturnal peregrinations ; and the realisation 

 of this fact was of considerable help to me in suitably arranging 

 the position of the fungus fruit-bodies which I wished the slugs 

 to visit. 



It has been calculated that an average-sized snail of moderate 

 pace progresses at the rate of about a mile in 16 days and 14 hours. 2 

 This works out at about 13-3 feet per hour. The rate of movement 

 of Limax maximus is probably not very different from that of a 

 snail. On one occasion I found that a Limax maximus had travelled 

 Irom one point to another 12 feet distant in 1 hour and 20 minutes ; 

 but the course taken was not the shortest possible, so that I have 

 no doubt that the actual pace of the slug somewhat exceeded 

 10 feet an hour. 



Phallus impudicus the Stink-horn Fungus as every botanist 

 is aware, is one of the most remarkable of all fungi. The young 

 fruit-body sometimes known as a Devil's Egg is a soft spherical 

 white ball, a little larger than a hen's egg ; and it is protected upon 

 its exterior by a thick gelatinous peridium. At maturity, the 

 ball suddenly bursts at the top, and then there emerges from it in 

 the course of about half an hour a sort of Jack-in-the-Box made 

 up of a long, white, hollow, spongy, bread-like stipe bearing at its 

 free end a conical cap covered with dark green slime (Fig. 80). 

 The slime contains sugar and millions of green spores, and from it 

 issues a very powerful and offensive odour. Dung flies are attracted 

 to the fungus by the smell, alight upon the green cap, lick up the 

 sweet slime, and carry away the spores upon their straggling legs 

 and inquisitive proboscides and within their alimentary canals. 

 1 A. H. Cooke, loc. cit., pp. 34-36. 2 Ibid., p. 46. 



VOL. II. Q 



