1922] 



Walker: Structure of OrtJiopteroid Insects 



25 



drawn from a potash preparation, they are shown in a com- 

 pletely inverted position, but this is a position that is prevented 

 in life by the mass of muscles which surround the spermatophore 

 sac. 



The mouth of the spermatophore sac is bounded below by a 

 single, large ventral lobe, which is slightly chitinized and 

 densely spinulose. In the retracted condition a deep transverse 

 pocket is formed beneath the ventral lobe. 



Fig. 5. 



Fig. 5. Genitalia of male Orthoptera, diagrammatic median sagittal sections. 

 The dotted lines indicate structures not in the median plane, a, Ceuthophilus, 

 retracted; b, same, everted; c, Neduba; d, Gryllid, based on Gryllus; 

 e, Acridid, based on Dissosteira and Melaywplus. For lettering, see page 71. 



On the roof of the penis there is a pair of small openings with 

 ■chitinized margins, leading into narrow tubules (Fig. 25), which 

 appear in sections to be partly glandular, but whose lining 

 cuticle is minutely pubescent. In sections of specimens with 

 everted parameres they are drawn backwards into the cavities 

 of the latter. These structures have apparently no homologues 

 in the other types of Orthoptera studied. 



