12 THE RICE GRASSHOPPER 



As is well known, female grasshoppers possess two 

 ovaries and it is an interesting point to ascertain whether, 

 during the act of oviposition, the eggs come alternately 

 from right and left ovary, or whether one ovar}' is emptied 

 first followed hy the other. As far as we are aware, no 

 observations have been made on this point among grass- 

 hoppers, but Wheeler, in his studies on oviposition in the 

 cockroach PJiijUodroinia, has shown that there the eggs 

 come alternately from the two ovaries. In the case of 

 the Kice G-rasshopper, the opposite of this seems to occur. 

 A female, killed during the act of oviposition after seven 

 eggs had been laid, and dissected, showed that all the eggs 

 had come from the left ovar}', the right ovar^^ being still 

 quite full. It seems probable, therefore, that in the case of 

 the Rice Grasshopper, one ovary is emptied of mature eggs 

 before any pass down from the other. 



The number of eggs in an egg-mass varies very great- 

 ly, and this is probably associated with the fact that the 

 female Hieroglyph us lays more than one mass. Although 

 no observations ha^e been made on this point, it seems 

 hkely that the first one or two egg-masses laid contain 

 more than those deposited later. The following record of 

 observations gives an approximate idea of the number of 

 masses laid per individual and the number of eggs per 

 mass. 



1. Nine females in breeding cage with males. Copulation first 

 ■observed 14th October, 1910. First egg-mass found 29th October, 

 1910. By 17th January, 1911, all grasshoppers were dead. On 30th 

 •January, 1911, soil was examined, and thirty-four egg-masses were 

 found. This, with an egg-mass previously removed, gives a total of 

 thirty-five egg-masses laid by nine females, or almost four egg-masses 

 per individual. 



The lengths of these egg-masses were as follows : — 



9 — 9 h nmi." ... ... 3 egg-masses 



10— lOi „ ... ... 5 



lU „ ... ... 3 



12 „ ... ... 14 



13 „ ... ... 2 



14 „ ... ... 2 



15 ,, ... ... 5 



Total ... 34 



Number of eggs per mass was as follows : — 



53, 45, 44 (2), 43, 42, 41, 36, 35 (3), 34, 32, 31, 30, 28 (3), 26 



1 One inch =25 mm. 



