LOCUSTA OVIPOSITOR 



3^5 



Development of ovipositor of 

 Locusta viridissinia : a, terminal seg- 

 ment ; a', cerci ; a", secondary division 

 of terminal segment ; h, penultimate 

 (ninth) segment ; h', primary papillae 

 of this segment ; h", secondary divi- 

 sions thereof; c, eighth segment ; c', 

 its papillae. (After Dewitz. ) A, 

 embryo ready for emergence ; B, 

 portion of integiiment of the ventral 

 plates of eighth and ninth segments ; 

 C, the appendages in a condition 

 somewhat more advanced than they 

 are in A. 



to one another, on the middle of the ventral aspect of the true 

 ninth abdominal segment, are 

 seen the two papillae {h'), which 

 at first are the only visible indi- 

 cations of the future ovipositor. 

 If, however, the integument be 

 taken off and carefully examined, 

 it will be found that there exist 

 on the eighth abdominal plate 

 two spots, where there is a slight ^^- 191 

 thickening and prominence of 

 the integument (Fig. 191, B, 6'). 

 From these two spots the two 

 lower rods of the ovipositor are 

 produced ; tliese two, together 

 with the two growths from the 

 ninth segment, form the four ex- 

 ternal rods of the ovipositor. 

 Inside these there exist in the 



completed structure two other rods (Fig. 192, B, ?)"). These are 

 produced by a growth from the inner parts of the two papillae 

 of the ninth segment. The relations of the six rods in their 

 early condition are shown in Fig. 191, C, where the two primary 

 papillae V of the ninth segment are seen with their secondary 



Fig. 192. Structure of 

 ovipositor of Locusta 

 riridissivia : A, ar- 

 rangement of parts at 

 base, c' being separated 

 and turned outwards ; 

 B, transverse section. 

 The parts of the ap- 

 pendage bear the same 

 lettering as in Fig. 191. 

 (After Dewitz. ) 



offshoots h" ; c' being the papillae of the eighth segment. The 

 subsequent relations of the pieces are shown in Fig. 192; A 

 exhibiting the base of the organ with the lower rods turned 

 on one side to show the others, the shaded parts indicating 



