166 THE COCKEOACH. 



To see the stigmata, examine from the ventral surface, 

 stretching the abdomen slightly. The stigmata are at the 

 apices of small backwardly projecting spout-like processes, 

 which lie just beneath the anterior angles of the several terga. 



C. The Appendages. 

 1. The head appendages are four pairs. 



a. The antennsB are very long, slender, many -jointed, 



and freely movable filaments, inserted into a 

 pair of oval arthrodial membranes just in front 

 of and below the eyes. 



To see the next three pairs of appendages, fix the animal 

 down on its back by means of a pair of small pins passed 

 through the sides of its prothorax. Bend the ventral part of 

 the head fonvards, and fix it in that position by means of 

 crossed pins. 



Examine the appendages in situ, noting their positions. 



Bemove the whole of the labium {sMto f g, fig. 37) without 

 injury to the structures beneath it. Mount it in glycerine. 



Similarly remove and mount the right first maxilla and 

 the light mandible. 



b. The mandibles are a pair of stout jaws, strongly 



toothed on their inner margins, and working 

 sideways. They lie immediately below the genae, 

 and articulate with the epieranium and with the 

 clypeus. 



c. The first maxillae are situated behind the mandibles. 



Each consists of the following parts. 



i. The protopodite consists of two segments, the 

 cardo or proximal piece and the stipes or distal 

 piece. 



ii. The endopodite has two divisions, an inner and 

 an outer. The inner division, or lacinia, is a 

 hard blade pointed at the end, and provided 

 with stiff setse along its inner border. The 

 outer division, or galea, is softer and is elon- 



