432 MR. LUBBOCK ON THE THYSANURA. 
Length ith of an inch 
O"" 8 
Common in Kent, under logs which have been felled and left lying among long 
grass and underwood. 
I take this opportunity of expressing my thanks to my two neighbours, Messrs. 
Janson and Solly, who have not only allowed me free access to their woods, but have 
also arranged logs of wood to serve as protection to the Smynthuridae. These facilities 
have enabled me to obtain plenty of specimens, and have saved me a great deal of time. 
They feed principally on the spores and first shoots of Fungi. Many specimens were 
infested by a small mite, which adhered to the underside of the body, and was sometimes 
present in considerable numbers. 
The hairs, which cover the head as well as the body, stand at a distance of abont 
•0047' from one another. They are gently curved, about -0075" in length, and 
roughened with small asperities or projections. The larger hairs on the antennae are of 
the same size and structure, while those on the legs are smoother. 
The eyes, as in all the species of the genus, are eight in number on each side. The 
anterior five are arranged in a quincunx, which is not quite regular, however, one of the 
posterior pair being a little too far back ; the other three form a triangle. This arrange- 
ment agrees with that figured by M. Nicolet as characteristic of the genus (I. c. pi. ii. 
fig. 26) ; but in the present species the eyes are nearer together than in his figure, and 
agree indeed even more closely with his representation of those of Cyphodeirus (I. c. pi. ii- 
fig. 22), especially as in that genus he makes the eyes pretty uniform in size, whereas in 
Smynthurus he represents the central eye of the quincunx as much smaller than the 
others, which is not the case in this species. 
The antennae are -047 5" in length, of which the terminal (so-called) many-jointed 
portion forms nearly one-half. The basal segment is cylindrical and quite short, being 
•004" in breadth, and only -005" in length. The two following segments are ' of 
nearly equal size, being each about -012" in length and *002" in breadth. On 
the whole they are cylindrical ; but their outline, and especially that of the third, is 
somewhat knobby. They bear a few scattered bristles, resembling those on the head and 
body, and also a few smaller hairs near their apices. The terminal portion of the antenna 
resembles a necklace of beads welded together, and gradually diminishes in size at the 
tip, though, for the greater part of its length, it has a diameter across the beads of 
•0015". At each projection is a whorl of small hairs, and at the apex are a few rod-like 
hairs, resembling those found on the antennse of so many Insects and Crustacea, and 
which are doubtless organs of sensation, though I was unable, from their minute size, 
to ascertain their structure in a satisfactory manner. 
The descriptions given by different naturalists of the mouth-parts of these animals have 
been very dissimilar. Pabricius mentions mandibles and maxillae, labium and two 
pairs of palpi, consisting respectively of five and three segments. Latreille does not 
hesitate to characterize this description as being " absolument Active." Assuredly it is 
absolutely incorrect ; but is it not more probable that Eabricius should have mistaken the 
species he examined, than that this great naturalist should have voluntarily committed 
a fault so certain of detection ? 
