ENTOMOLOGY. 
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in the latter case., they are called spurs (calcaria). 
The spinous processes are often arranged in a double 
row on each side of the tibia beneath, having a kind 
of groove between them ; the spurs are most fre- 
quently placed in pairs at the extremity or middle. 
The prevailing arrangement is two at the extremity 
of each of the tibiie ; sometimes there is only one, 
and not rarely two on the middle and hinder tibiae, 
and one on the anterior. 
The terminial division of the leg is the tarsus or 
foot, which consists of a series of small, usually 
heart-shaped or triangular joints, never exceeding five 
in number. It is connected with the tibia by gin- 
glymus, and the joints are closely united to each other, 
so as to present a uniform surface beneath. It admits 
of considerable flexure, a property indispensable for 
executing the functions that have been assigned to it. 
The first joint is in general longest, and the last next 
to it in length ; the fourth (which is often hilobed) 
shortest. The terminal joint is commonly clavate, 
and bears either one or two claws at the tip ; the 
latter number being by far the most general. These 
claws are simple, bifid, dentate on their under edge, 
or serrate. Between the claws we often perceive « 
smaller one, which is named the spurious claw 
( pseudonychia ), and in many families two small 
membranous cushions are present, which act like 
sucking cups, and enable the insect to support itself 
against gravity. Membranous lobes of a similar 
kind are frequently attached to the underside of the 
tarsal joints. The whole of the underside (or sole- 
