Legs of Reduviidae show modifications and specialised structures adapted for their predatory habits and e~cient prey capture. The variable forelegs of these insects apparently reflect the correlation between the structure of the legs and the types of prey. The tibial pads or fossula spongiosa are a common feature in the forelegs or fore-and midlegs of most of subfamilies of Reduviidao. The functional morphology of the tibial pads of the foretogs of three insects, Haematorrhophus nigroviolaceus (Router), Pirates affinis S~rville and Triatoma rubrofasciata (Do Goor) has been studied. The oily substance produced by the cushion-like secretory tissue and the minute tenet hairs on them increase the ability to sustain static tension and enhance the gripping efficiency of the legs. Scanning electron micrographs reveal distinct morphological variations among the tibial pads. In addition to the shape and size of the organs, the number, structure and density of the tenet hairs on them markedly vary. The ability of the foretibial pad to sustain static tension on smooth and rough surfaces has been found to differ among the insects studied and this is remarkable in predatory insects.

The predatory bohaviour of three reduviids, the mUlipede-feeding Haematorrhophus nigroviolaceus (Router) (Ectrichodiinao), the insectivorous Pirates a.~nis Serville (Piratinae) and the haematophagous Triatoma rubrofasciata (De Geer) (Triatominae), both under natural and laboratory conditions, is discussed. Visual stimuli elicited by the moving prey appear important for the initiation of feeding response. The olfactory stimuli from the defensive secretions of the prey appear to enhance the response and help in the continuation of feeding. In the haomatophagous Triatoma rubrofasciata, while feeding responses are elicited only by the temperature gradient around their vertebrate hosts, the visual and olfactory senses play only a minor role. On the basis of observations on feeding behaviour, appropriate predatory bohaviour models for the three reduviid species have been constructed.

Feeding behavioural studies of many exclusivelypredatory species exhibit c1earcut stimuli-response mediated sequences and these can be categorised into distinct sub-units like: search and location of prey ....approach and attack: of prey ....immobilisation of prey ....transportation of prey to safe place ....consumption of prey. These feeding behavioural activities differ among reduviids particularly with respect to prey types. These bugs are endowed with many structural, physiological and behavioural adaptations for efficient predation.The ovipositional behaviour of reduviids in different habitats also shows considerable variation and their reproductive strategies include selection of suitable sites to assure successful emergence and development of young ones and so far very few egg predators and egg parasites have been reported for these terrestrial insects.

Eggs of Piratinae are unique among reduviids in possessing stellate chorionic filaments that remain exposed even after the insertion of the egg into the ground. These eggs have developed many structures for supplying ambient oxygen to the developing embryo inside them. The ultrastructure of the chorion, the operculum and the aero micropylar system of the eggs of seven species of piratinae bugs are reported.

Anatomical and histological studies of the alimentary organs of sixteen reduviids, with diverse food habits indicate structural variations. The terminal part of the tubular second midgut of these predaceous insects has a permanent sac-like region with distinct histology, concerned with absorption of digested food. In addition, the digestive system is characterised by a reduced pylorus with pyloric-intestinal and pyloric-rectal valves, surrounded by flask-shaped ampullae of the four malpighian tubules. The ampullary cells with their filamentous apices and with fibrillar cytoplasmic processes are concerned with. water absorption. Commonly in all these terrestrial insects, the anterior end of the rectum also bears a well-developed, inverted cup-like rectal gland, the cells of which also absorb water from the excreta stored in the impermeable, intima lined rectum. Members of Ectrichodiinae show simple ampullary cells and a unique rectum, reported for the first time among reduviids with scattered dome-shaped glandular cells as found in Homoptera and in some phytophagous Heteroptera. The simple nature of the alimentary organs indicates its primitive organization within the reduviid subfamilies.