ENTOMOLOGY. 119 



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 tibiae ; 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 bilobed) 

 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. 



