254 PREDACIOUS AND PARASITIC 



parts of the abdomen, where they are attached to the various 

 muscles by which the parts of the organ are actuated. The action 

 of the outer lancets appears to be of a rasping rather than a cut- 

 ting nature, and as, in the instances of which I have definite 

 knowledge, the eggs are placed upon the surface of leaves, it seems 

 likely that the function of these organs is to roughen the surface, 

 or to irritate it, so as to render it fit for the reception of the eggs. 



The Internal Anatomy. 



The alimentary organs are of a much simpler type than obtains 

 in those insects which have been hitherto described in these pages. 

 The suctorial tube of the rostrum passes on the juices which it 

 has extracted from the victim through a pharynx surrounded by a 

 mass of spiral muscles to an oesophageal passage, which receives 

 in its course the secretion of two or four attached glands, which 

 may be presumed to be salivary in their functions. There is no 

 organ in any way analogous to the sucking stomach of the diptera, 

 but the juices pass directly to an elongated vessel which answers 

 the purpose of stomach and intestine, but in which it is difficult to 

 allocate the limits of the respective functions. Some vessels dis- 

 charge into this organ at a point which is probably the termination 

 of the stomach proper. It has been suggested by Burmeister that 

 these are of a urinary nature, but from their position and structure 

 in the specimens, which I have examined, I should be more 

 inclined to think they may be biliary in function, if I ventured to 

 differ from so responsible an authority on insect anatomy. 



The intestine terminates in a short, slightly expanded tube, 

 which opens at the extremity of the abdomen, forming the anal 

 orifice. In the female the sides of the abdomen are occupied by 

 the ovaries, in which the elongated eggs lie clustered in an oblique 

 position, ready for their passage to the ovipositor. I have always 

 observed that the ova are all about the same size and apparently 

 equally developed, while I have not found any appearance of 

 immature or rudimentary ova which, by successive development, 

 would keep up the supply. From this it would seem that the eggs 

 of these insects must be comparatively few in number, and that 

 the first development of the ovaries probably represents the extent 

 of the maternal effort. The spermathecse which are mentioned by 



