430 MR. LUBBOCK ON THE THYSANURA. 
of the group; but while there is so much difference of opinion on the subject 
might reasonably have supposed that they would have been carefully studied by our 
naturalists. Suspected, however, of having passed the Rubicon of Entomology, and of 
not being true and proper Insects, they have been not only neglected, but absolutely 
ignored by our entomologists; so that, to my amazement, I found that (excepting a 
verv brief notice of Fetrobius maritimus, by Dr. Dickie *) Dr. Leach's original description 
of that species f, and Mr. Templeton's $ " description of the Irish species of Thysanura," 
with an introduction by Mr. Westwood, are the only British contributions to the natural 
history of this group § . We have thus not added a single fact to the anatomical and 
other details given by Continental observers, and we have at this moment only sixteen 
Irish and actually only one English species recorded. When it is considered that these 
animals are easily preserved, are in many cases prettily coloured, are numerous in winter, 
when the field-naturalist is less distracted by the number of objects than at other times 
of the year, and, finally, that they are so common that it is impossible to pick up a hand- 
ful of dead leaves, or turn over an old I02 of wood, without disturbing many of them, I 
think that every one must be astonished at the neglect they have experienced ; and I hope 
I need make no further apology for calling the attention of the Society to this subject. 
The Thysanura have generally been divided into two families : — the Lepismidae, cha- 
racterized principally by the presence of many-jointed appendages at the posterior end of 
the abdomen ; and the Poduridae, which have on the under side of the abdomen a flexible 
spring, by means of which they can jump to a considerable distance. 
M. Nicolet proposes to divide the Poduridae into three tribes,— the " Smynthurelles," in 
which the body is more or less globular ; the " Podurelles," in which it is linear, and 
composed of eight or nine segments ; and the " Lipurelles," in which the springer is 
absent or rudimentary. These three groups seem to me to constitute three well-marked 
families, which would naturally bear the names Smynthuridae, Poduridae, and Iipuridae. 
For the present, however, I confine my remarks to the Smynthuridae, and must deter 
the consideration not only of the natural position of the Thysanura in the animal king- 
dom, but also of its division into families, until I shall have had time and opportunity 
to make a thorough examination of the whole group. 
SMYNTHURUXffi. 
The characters attributed by M. Nicolet to his " Smynthurelles " are as follows : 
Body globular or ovoid. Thorax and abdomen forming one mass. Head vertical or 
inclined. Antennae of four or eight segments ; elbowed at the middle. Sixteen eyes, 
eight on each side, situated on a black patch, a little behind the antennae, and on the top 
of the head. Legs long and slender. Saltatory appendages with a supplementary 
segment. 
Brit. Assoc. Report, 1855. t Zool. Misc. vol. iii. % Trans. Ent. Soc. vol. i. 
§ Since the above was written, Mr. Westwood has kindly called my attention to Samouelle's ■ Entomologist's Useful 
Compendium' (1819). In this volume (pp. 140, 141) five species are recorded, viz. Lepisma saccharine, Forbtcina 
polypoda, Petrobius maritimus, Podura plumbea, and Smynthurus fuscus. 
