BY K. J. TILLYARD. 



427 



fied, with a view to the laying of the eggs in the loose sand. 

 The eighth, ninth, and tenth segments are more or less fused 

 together, forming the projecting end of the abdomen; of these, 

 the ninth segment is terminal, the reduced tenth being situated 

 more dor sally upon the eighth, and carrying the anus, as in 

 Text-fig. 3, an. The ninth segment is flattened from side to side 



Text-fig. 3. 

 Ithone fuscn Newra., i. End of abdomen, «, Lateral view; A, posterior 

 view; an, anus; ap, tactile appendage or gonopod; g, gonopore or 

 genital opening; j>*, psammarotrum or sand-plough; 7, 8, abdominal 

 segments. ( x 12'. 



to form the unique psammarotrum or sand-plough, with which 

 the insect ploughs the loose sand while ovipositing. From the 

 base of this segment, on either side, there projects downwards an 

 unjointed appendage, ending in a rounded tip with numerous 

 hairs; these, though very like cerci in appearance, must be true 

 gonapophyses or gonopods, from their position; they clearly act 

 as feelers during oviposition, and must be homologous with the 

 more elongated but otherwise similar organs in the females of 

 Berothidce. 



Types: Holotype of £ in British Museum Coll., from New 

 Holland; presented by the Entomological Club; described by 

 Newman in 1838(6). Allotype $ in Coll. Tillyard; this sex not 

 having been previously described, I have selected a fine speci- 



