from the Island of Madeira. 375° 
extremity, outer side, and base; they are terminated by several 
curved pointed processes, and have a yellowish-red hue, that of 
the margins being brown, The abdomen is oviform, convex 
above, with a conical protuberance on the upper part of each 
side, which is nearly equidistant from both extremities; it is 
densely clothed with coarse hairs, and projects over the base of 
the cephalothorax ; its colour is dull yellow, with a brown band 
extending along the middle of the upper part, which tapers to 
the spinners, and is somewhat ramified ; the lateral protuberances 
have a faint tinge of orange, and the sides are marked with 
oblique, slightly curved, dark-brown lines; the under part has 
a dark-brown hue mingled with dull yellow, and is broadly 
bordered laterally with yellowish white: the spinners are eight 
in number; those constituting the inferior pair, which are the 
shortest, consist of a single joint each, and are united through- 
out their entire length. 
Arachnologists have experienced much difficulty in assigning 
to Mithras paradoxus, the type of the genus, a satisfactory posi- 
tion in the systematic arrangement of the Aranezdea ; nor is this 
at all surprising, as its appearance is very anomalous, and long 
after its discovery it was generally supposed to have only six 
eyes. It is now known to possess eight organs of vision; and 
if, as is in the highest degree probable, it and the Mithras un- 
dulatus of M. Koch should be found to have four pairs of spin- 
ners and calamistra, every difficulty with ‘regard to their classifi- 
cation will be removed; for in that case they, together with 
Mithras flavidus and Mithras dubius, must undoubtedly be placed 
in the family Ciniflonzde, immediately after the genus Veleda. 
Mithras dubwus. 
Length of the female 55th of an inch; length of the cephalo- 
thorax z1;; breadth ;,; breadth of the abdomen 4; length of 
an anterior leg +; length of a leg of the third pair +4. 
The cephalothorax is short, broad, somewhat oval, convex, but 
depressed at the base, prominent and rounded in front, and has 
two furrows on each side directed obliquely upwards ; it is thinly 
clothed with short yellowish hairs, and of a dark-brown colour, 
being palest in the medial line and immediately above the lateral 
margins. In the disposition and relative size of its eyes it re- 
sembles Mithras flavidus. The falces are short, subconical, and 
vertical ; the maxillz are powerful and greatly enlarged at the 
extremity, which is protuberant on the inner surface ; the lip is 
triangular, and the sternum is oblong heart-shaped, with small 
eminences on the sides opposite to the legs. These parts are of 
a dull brownish-yellow colour, the sternum, which is the darkest, 
having its extremity and lateral margins of a dark-brown hue, 
27% 
