764 



HEMIPTERA 



lunar, with two rounded horns. The dorsum is raised in the median 

 hne. The mesothorax is triangular, with the apex posteriorly. 

 The metathorax is covered dorsally by the elytra, which are two 

 small chitinous plates belonging to the mesothorax, but consist of 

 clavus, cormm, empodium, cuneus, and membrane. The abdomen, 

 which IS rounded m shape, with seven segments and an eighth anal 

 appendage, is broadest opposite the third segment. Posteriorly it 

 is covered with round hairs. Length, 5 to 6 millimetres. Male 

 smaller than female, with penis flexed into a notch between seventh 

 and eighth segments. 



Internal Anatomy— The mouth leads into the pharynx, beneath 

 which is a syringe organ or salivary pump, into which the salivary 

 glands open. The pharynx leads via the oesophagus into a large 

 crop. There is the usual mid-gut, intestine, and rectum. 



Life-History. — They live in cracks in floors, walls, and furniture 

 during the day, and issue forth at night to suck blood from human 

 beings. They are capable of emigration from house to house. 

 The female lays some fifty eggs three or four times a year. Com- 

 plete development is said to require eleven weeks, but may be 

 completed in as short a time as seven weeks. 



The eggs, which are oval, i*i2 millimetres in length, and white in 

 colour, take about seven to ten days to hatch. The larva grows 

 slowly, moulting about five times, at intervals of about eight days, 

 after which the wing-pad appears, showing that the adult stage 

 is reached. They feed only upon blood. 



Bionomics— 5^7^. — In biting, they extend the proboscis, and feel 

 about, testing the skin with the delicate hairs, then pierce it by 

 the stylets, and inject saliva by the syringe, causing congestion of 

 the area, when the blood runs up the grooves in the stylets by 

 capillary attraction into the pharynx. 



Fig. 373. — Clinocovis lecfularius 

 L.: Male, (X to.) 



Fig. 374. — Clinocons lectularius 

 L.: Female. (X 10.) 



