INTERNAL STRUCTURE OF THE GRASSHOPPER. 263 



li. The reproductive organs. 



1. The ovary (Fig. 139, o) is a long white gland, situ- 

 ated above the ventriculus and ilium. It is made up of two 

 sets of tubes or ovarioles, which are bound together into 

 a compact mass. When this mass is carefully examined 

 with a lens the two sets of tubes wiU be seen to run up- 

 wards, forwards and towards the median line. 



(i.) Near the posterior end of the ovary these tubes 

 communicate with two delicate transparent oviducts, which 

 run down around the posterior end of the ilium to the 

 ventral surface of the body. 



(ii.) Here they unite to form a single median tube, the 

 vagina, which opens externally upon the upper surface of 

 the sub-genital plate. 



2. On the median line, between the internal plates of 

 the ovipositor, there is a second much smaller external 

 orifice, which communicates with a long slender convoluted 

 tube, which opens into a small white pouch, the sper- 

 matheca (Fig. 139, s), which lies above the posterior end 

 of the vagina. 



i. The nervous system. 



1. On each side of the ingluvies notice a small white 

 stellate spot, the gastric ganglion (Fig. 139, sg), radiating 

 from Avhich are a number of small nerves and a larger 

 commissure, which may be traced forwards into the head, 

 where it joins. 



2. The supra-cesqphageal ganglia, which are situated 

 between the eyes, in the upper surface of the oeso- 

 phagus. 



3. From them a pair of short commissures run down, 

 forming a collar around the cesophagus, to the ventral 

 nerve chain. This consists of commissural fibres, with 

 the following ganglionic enlargements : — 



