426 
CLASS ARACHNIDES. 
more narrowed at its base, dilated and rounded towards the 
end; the first pair of feet is the longest; the fourth and second 
are almost equal ; the third is the shortest. 
Ctenus, Wald., 
Have the eyes disposed on three transverse lines, 2, 4, 2, and 
forming a sort of curvilinear triangle, inverted, and truncated 
before or at its point ; the tongue is square, and almost isome- 
trical ; the fourth pair of feet, and, next to them, the first, are 
the longest ; the third is the shortest. 
This genus has been established on a sort of arachnid, 
tolerably large, which is found at Cayenne. Some others 
have been since discovered, either at the same colony, or at 
Brazil, but all unpublished. 
Dolomedes, Lair., 
Whose eyes, disposed on three transverse lines, 4, 2, 2, re- 
present a quadrilateral, a little broader than long, with the 
two last, or posterior ones, situated on an eminence, and 
which have the second pair of feet as long, or longer than the 
first ; those of the fourth are the longest ; the tongue is square, 
and as broad as high, like that of Ctenus. 
Some have the two lateral eyes of the anterior line larger 
than the two comprized between them, and the abdomen in 
an oblong oval, and terminating in a point. 
The females construct at the summits of trees loaded with 
leaves, or in bushes, a silken nest, in the form of a funnel or 
bell ; lay their eggs there, and when they proceed to the 
chase, or are forced to abandon their retreat, they always 
carry with them their cocoon, which is fixed upon the chest. 
Clerck tells us that he has seen individuals leap very promptly 
on flies which were hovering around them. 
The others have the four front eyes equal, and the abdomen 
oval, or rounded at the end. 
