THE NAUTILUS. 21 
This classification is, to a certain extent, provisional; and may 
have to be somewhat modified when we have a fuller knowledge of 
the anatomy. Whatever else may be said of it, the principle 
adopted is the right one, and the only one which modern science 
can recognize. The arrangement of the Adams brothers is largely 
artificial, both as to genera and subgenera, as well as the system 
adopted by Lea, as they bring together side by side, species and 
groups from every country which have no close relationship what- 
ever, and by such methods anatomical and conchological characters, 
the facts of geographical distribution, habits and palzontology, are 
ignored, 
THE SMALL GREY SLUG IN JAMAICA. 
BY T. D. A. COCKERELL. 
Some days ago Mr. W. Harris sent me from Cinchona some 
strawberry plants, together with a beetle larva which was injuring 
them. Of this larva there will be more to say hereafter, but the 
object of the present note is to record that among the plants I found 
three specimens of the small, grey slug of Europe, A griolimax agrestis. 
This slug, well-known as a garden pest in England, has never before 
been noticed in the West Indies, and there can be no doubt that it 
has been introduced with plants. It is, I suppose, almost impossi- 
ble to import living plants without sooner or later introducing for- 
eign slugs. They and their eggs come in the earth about the roots, 
and, in many cases, it must be practically impossible to detect them 
on arrival. It might be advisable in some cases to isolate newly- 
arrived plants by water, and search for slugs on them at intervals; 
or we might import the carnivorous slug, Testacella; or introduce 
some of our native carnivorous snails, Oleacina, into the locality 
where the plants were being propagated. It has been recorded that 
in twenty-four hours, 25 specimens of Testacella devoured 25 earth- 
worms and 25 Agriolimax agrestis. 
The small, grey slug, although now first detected here, has 
spread to many distant localities by human means. I have seen 
specimens from yarious parts of the United States, west to the 
Pacific coast and east to New Jersey, from St. Helena, the Canary 
Islands, Tristan d’Acunha, New Zealand, etc., and no doubt in time 
it will inhabit every part of the earth in which the climate is suit- 
