296 OBSERVATIONS ON THE 
affords manifest evidence of design, and, consequently, 
of an intelligent designing agent. 
A more exact idea of the mechanism of the cala- 
mistrum than can be conveyed in words will be ob- 
tained by inspecting Plate I. figs. 1 and 2*. 
Distinguished naturalists have represented spiders 
as having their tarsi armed at the extremity with 
three claws, which occupy the upper and anterior 
portion of the foot. That this is the case with many 
species cannot be denied ; other species, however, be- 
longing to various genera (J/ygale avicularia, Clubiona 
erratica, Drassus nitens, Hecaérge spinimana, Philo- 
dromus dispar, and Salticus scenicus, for example), 
have only ¢wo claws on each foot ; and if the tarsi of 
the larger Geometric Spiders indigenous to Great 
Brita, such as Epetra umbratica, Epeira quadrata, 
Epeira diadema, and Epeira apoclisa, be examined 
under the microscope with a highly magnifying-power, 
it will be distinctly perceived that the inferior part of 
- their feet is provided with several claws, which have 
a considerable degree of curvature, are finely pointed, 
and are furnished with tooth-like processes on the 
underside (Plate I. fig. 3); and should the investiga- 
* The calamistrum of some small spiders belonging to the 
genera Hrgatis, Mithras, &c. ‘consists only of a single row of 
curved, movable bristles; and the proximate extremities of their 
additional or fourth pair of spinners, unlike those of the larger 
species of the genus Ciniflo, are not separated by a septum, but 
are usually without any definite mark of distinction. 
