Ixii INTEODUCTION. 



vulva, and it is mostly surmounted by a hirsute cauda, 

 or anal style. 



Dissimilar or asymmetrical appendages are attached 

 to the oviduct. First, the spermal pouch, or sperma- 

 theca; and, secondly, the two collaterial glands ; which, 

 as in Aphis, seem either to lubricate the egg as it passes 

 through the oviduct, or else to secrete the glairy 

 covering, which, at first yellow, afterwards darkens in 

 colour by exposure to the air. In Tettigonia there 

 appears to be an additional vascular pouch to the 

 oviduct, the significance of which is not clear.* 



The ova of the sub-tribe I denominate ' Silentes ' in 

 my Synopsis (p. xxxiv), are remarkably large for the 

 size of the insects, and they do not appear, in their 

 mature state, often to number more than a dozen, and 

 in some species even less. 



In ' Stridulantes ' they generally occur by hundreds in 

 the same female. The eggs have a tough covering, 

 and when recent are sufficiently transparent to show 

 the germinal spot within, and subsequently the usual 

 yolk segmentation. 



Touch and Taste in the Tettigid^. 



The possession of a true tongue, and the presence of 

 salivary glands in some insects, and also the fact that 

 honey is greedily sought by them, must lead to the 

 conclusion that they have some kind of taste-sense. 

 Some insects have this tongue soft and continually 

 moist, which would seem to be a necessary condition 

 of an organ fitted to appreciate flavours. The Tetti- 

 gida3 seem to have no obvious taste-organs with papillcT, 

 other than salivary vessels and glands. 



Such vessels may be more easily dissected out from 

 the soft juicy bodies of the Aphrophoridae, or Cuckoo- 

 spits, than from the attenuated bodies of the Jassidae, 

 &c. As might be expected, these glands are most 



'■'■ Burmeister, Transl. Shuckard, p. 191. 



