BY W, K. COLLEDGE. 53 



the muscular structure of the victim is sawn around the point, 

 the aperture is kept clear and a freer flow of blood insured I 



madea little glass cell, big enough to hold a mosquito, and capable 

 of being strapped to the finger, or on any other object, and of 

 being placed on the stage of the microscope at the same time, and I 

 found that thcj could not pierce the fruit of the fresh pineapple 

 They could freely suck up the juice, but when they tried to pierce 

 the fruit they failed. I could see the combined lancets bending 

 like a fishing rod under the force with which they were thrust 

 against the fruit, but it was too tough for them to penetrate. 

 ihe poison and salivary glands of this species are small and 

 delicate and difficult to separate in an uninjured state. They lie 

 in the prothorax contiguous to the neck, and appear like three 

 ong sacs, the central being the largest, and somewhat larger at 

 the base. They have a granular appearance, and are each 

 traversed centrally by a fine ductule, which collects the secretions. 

 ihe three ductules then unite, forming one tube which joins at 

 the neck, the tube proceeding from the opposite set of glands. 

 It passes along the under part of the head until the base of the 

 large sucking lancet is reached, where it terminates in a circular 

 cup. This is now on the screen, see Fig. 20, the lancet is magni- 

 fied so that It appears like the mast of a ship, and out of °the 

 centre of the cup there hangs the poison duct, looking like a 

 ship's cable. This enables you clearly to understand 



how the poison and salivary fluids are conveyed from 

 the glands to this tiny reservoir. When the lancet 

 IS thrust into the skin, that exertion probably injects 

 the poison fluid into the wound, then the suction 

 apparatus is brought into play. The base of the lancet curves 

 back in the shape of a tube, and then expands into a hollow 

 bulb or pump. Fig. 19. It really acts as a reservoir, and I 

 think the work of sucking is performed by the ringed muscles of 

 the aesophagus and proventriculus which are attached to .^piny 

 processes at the further end of the bulb. 



With regard to the function of respiration very elaborate 

 organs are used to ensure it The oxygen of the air is as 

 necessary for its existence as it is for us. We inhale air into 

 the lungs, the corpuscles of the blood extract the oxygen and 

 carry it to all parts of the body where blood vessels ao.' But if 

 we could empty out all the blood, and after filling all the 

 arteries and veins down to the minutest capillary vessels with 

 air, and send it circulating through the system, that would be 

 an iJliistration of the way in which injects breathe. The whole 



