THE SPIDERS. 181 
possessing several pairs of feelers like legs, of a thorax, to 
the three rings of which are attached three pairs of legs, 
and of a hinder, body, or abdomen, consisting of many dis- 
tinct rings. In the articulation of their body, the Solifugee 
are therefore in reality more closely related to flies than 
to other spiders. Out of the Devonian Primeval Spiders, 
which were nearly related to the Solifugee of the present 
day, the Long Spiders, the Tailor Spiders, and the Round 
‘Spiders probably developed as three diverging branches. 
The Long Spiders (Arthrogastres), in which the earlier 
articulation of body has been better preserved than in Round 
Spiders, appear to be the older and more original forms. 
The most important members of this sub-class are the scor- 
pions, which are connected with the Solifugee through the 
Tarantella (or Phrynidz). The small book scorpions, 
which inhabit our libraries and herbariums, appear as a de- 
generate lateral branch from the true scorpions. Mid-way 
between the Scorpions and Round Spiders are the long- 
legged Tailor-spiders (Opiliones) which have possibly arisen 
out of a special branch of the Solifugee. The Pycnogonida, 
or No-body Crabs, and the Arctisca, or Bear Worms—still 
cenerally included among Long Spiders—must be completely 
excluded from the class of Spiders; the former belong to the 
Crustacea, the latter to Ringed worms. 
Fossil remains of Long Spiders are found in the Coal. 
The second sub-class of the Arachnida, the Round Spiders 
‘Spheerogastres), first appear in the fossil state in the Jura, 
that is, at a very much later period. They have developed 
out of a branch of the Solifuga, by the rings of the body 
becoming more and more united with one another. In the 
true Spinning Spiders (Aranez), which we admire on 
