THE ENTOMOLOGIST. 263 
cannot say that I have verified it in England. On first 
emergence they are white or colourless, but in a very short 
time they are covered with a black, brown, or olive-coloured 
jelly, of offensive scent and disgusting appearance. Although 
Peck, Say, Harris, Bethune and others in America, De Geer, 
Réaumur, Bouché, Hartig and many others on the continent 
of Europe, and Mr. Westwood in England, have written on 
this loathsome grub, and although I have read their observa- 
tions with the attention they merit, 1 cannot say that I 
thoroughly understand the mode in which this jelly or 
mucilage is produced: it accumulates on the surface of the 
skin, until the creature becomes a dark mass without appa- 
rent life, or even organisation. ‘The slugs are first observable 
at the beginning of- July,—then of course very small; anda 
succession continues to make its appearance, and to iufest 
the leaves of sloe, pear, cherry or service, throughout August 
and September, and often far into October. ‘They glide with 
extreme slowness over the surface of the leaf, and partly by 
means of claspers, a pair of which are attached to the under 
side of every segment, except the Ist, 4th, and 13th. ‘These 
claspers seem to possess little of that prehensile property 
which is so striking a character of the claspers of the cater- 
pillars of moths and butterflies. In addition to the claspers, 
fourteen in number, which are situated on the under side of 
the abdomen, there are six articulated or thoracic legs. 
These, as well as the head, are invisible, except when the 
creature is crawling or feeding; indeed, these so-called 
organs of locomotion are concealed by the body and its 
concomitant slime or jelly, and their office seems to devolve 
on the annular segments of the body, which, by alternate 
dilation and contraction, effect the desired object. This 
phenomenon is observable in the larve of many other insects, 
particularly in those which are apparently apod, such as the 
maggots of flies and some Curculionide. The body is some- 
what swollen at the anterior extremity, and gradually 
attenuated towards the posterior, which is slightly raised,—a 
character frequently observable in this family of insects, as 
well as in the cuspidate Lepidoptera. During the greater 
part of their larval existence, these slug-worms seem quite 
destitute of that rambling propensity which is commonly 
observable in the larve of Lepidoptera; indeed, in them, 
