lOO JOURNAL OF CONCHOLOOY, VOL. lO, NO. 4, OCTOBER, I9OI. 



which was highly elastic, was increased about three inches in a minute. The slug 

 was white, and about one and a half inches in length. 



28. Daniel, J. E. Thread-spinning by Slugs, Toin. cit., p. 206. 



29. Jousseaume, F. Faune Malacologique des environs de Paris, 



Bull. Soc. Zool. France, 1876, pp. 31, 109-11. 

 Jousseaume observed the descent of "Li/nax gatidefroyi" =Arion 

 siihfusciis; and supposed, erroneously, that the mucus used came from 

 the caudal-gland. He also refers to the descent of ^'- Liiiiaceilafidva" 

 ^Liinax fulvt/s, Norm., and of '■'■ Limacella l>riifinea,"^Agrloliiiiax 

 hevis. The thread of the last-named attained a length of several 

 decimetres before breaking. 



30. Eimer, T. Ueber fadenspinnende Schnecken, Zool. Anz., vol. i, 



1878, pp. 123-4. 

 Eimer saw, in his garden, in the early morning sun, Agr. agrestis 

 lowering itself by a long thread from a leaf of a mulberry. It was 

 hanging at a distance of about a metre from the leaf. The thread 

 continued to increase in length, but the animal fell when about a foot 

 from the ground : the thread at that moment being about six feet long. 

 The author is the first to suggest that slugs chiefly spin when they find 

 it necessary to escape from exposure to the rays of the sun, etc. The 

 thought occurred at once, he says, that the slug, sitting upon the leaf, 

 had been surprised by the sun, and had adopted this means of with- 

 drawing from the unpleasant influence. On being placed on a grass 

 stem, held vertically in the hand and exposed to the sun, the creature 

 soon crept to the lower extremity, and became suspended on a thread, 

 which broke after attaining the length of about a foot. Eimer repeated 

 this experiment, and found that the slugs sometimes made a thread 

 and sometimes fell without one; both these cases happened when the 

 slugs had no chance of creeping into the shade; when they had this 

 chance they availed themselves of it. After communicating his 

 observations to the Wurtemberg Natural History Union, Eimer heard 

 from a correspondent that a gentleman, whose bean fields were much 

 infested with slugs, had dusted the creatures with lime, with the result 

 that each slug so treated crept quickly to the edge of the leaf on which 

 it was sitting, spun a thread, let itself down to the earth, and soon died. 

 Repeating this experiment, Eimer found that Agr. agrestis, when 

 dusted with lime, exhibited great alarm, and quickly descended by a 

 thread. 



31. Tye, G. S. MoUuscan Threads, J. Conch., vol. t, 1878, pp. 



401-15. 

 Tye repeats his paper (25), with additions including references to 

 Hoy (2), Shaw (3), Binney (20), and Harte (26). He had witnessed 



