38o 



PHYLUM ARTHROPODA 



eyes, and the antennae, which are furnished with numerous 

 sensitive structures, in great part olfactory. 



Alimentary system. — The cESOphagus is a narrow tube 

 which runs down the thoracic region. In the abdominal 

 region it expands into the crop or honey-sac. The crop 

 opens by a complicated orifice, with a remarkable stopper 

 arrangement, into the digestive region or chyle stomach, 



Fig. 215. — Nervous system of bee. — After Cheshire. 



A. Of larva. B. Of adult, a., Antenna ; mx., maxilla ; m., mandible ; 

 a'., origin of wing ; 1-5, abdominal ganglia. 



which is separated by a pylorus from the coiled small 

 intestine. The inner wall of the small intestine bears 

 numerous rows of chitinous teeth set in longitudinal ridges, 

 and is perforated by the apertures of the excretory tubules. 

 At the junction of the small with the large intestine there 

 are six brownish plates, perhaps functioning as valves. 



In connection with the anterior region oi the gut there is a very 

 complicated series of glands. First we have, in the workers only, on 



