558 ORTIIOPTERA. 



is under the eleventh ring in all the Orthoptera, according to 

 Lacaze-Duthiers' researches. The female genital armature is 

 farther complicated, in the Locustarice especially. The 

 eleventh segment is composed of five parts, which surround 

 the anus. 



Two of these are lateral filaments which are, in one case, as 

 in Mantis tessellata (Fig. 23), multi-articulate, and are proper 

 sensory organs, like the antennae, and must be regarded, in our 

 view, as homologous with the anal prop-legs of Lepidoptera and 

 other insects, and as true-jointed appendages like the thoracic 

 legs, and jointed appendages of the head, such as the palpi 

 and antennae. They also form the anal stylets of the Gryl- 

 lidce, etc. These anal stylets are articulated to the posterior 

 edge of the tenth tergite, as Lacaze-Duthiers states, and thus 

 seem to us to be properly appendages of that ring, which, as 

 this author affirms, "presents t^'O articulating teeth for this 

 purpose." The two other elements are "triangular, surround- 

 ing the anus with three valves, which, by their union, form a 

 sort of pyramidal body," which he calls the " subgenital or pre- 

 genital plate." There are then, two systems of appendages, 

 as we have before stated ; i. e., the genital armature, consist- 

 ing of two pairs of non-articulated stylets, and the single pair 

 of anal articulated stylets, which are the homologues of the 

 thoracic legs, together with the pre-anal plate. 



The same parts are present in the male, being converted into 

 large, clasping, hook-shaped stylets, for retaining a firm hold 

 of the female during sexual union. 



The eggs as they pass from the oviduct between the valves 

 are deposited in a hole in the ground, made by the powerful 

 ovipositor. Certain Locustarice imitate the Cicada in laying 

 them methodically in the stems of plants, which are drilled out 

 by the valves of the ovipositor, which are slightly toothed on 

 the outer sides and easity move on one another, somewhat as 

 in the Saw-fly and Cicada. "The eggs of the Gryllidce are 

 laid either singly in the ground, in irregular clusters in subter- 

 ranean passages, or uniformly in a single row, in the pith 

 of twigs; those of the Locustarice are never laid singly, 

 but either in the pith of plants, in regular clusters in the 

 ground, or in regular rows on stems of plants ; those of the 



