The prey is held {250}firmly in the formidable trap formed by the anterior leg, and is thus brought near the mouth. The _Mantis_ usually commences its feast by taking off some portions of the head of its wretched victim, and displays an absolute indifference to its struggling or kicking; the mandibles having seized a portion of the food, the legs holding it move away, thus leaving a fragment in the mouth. Portions only of a captured Insect are consumed, much being cast away; and Mr. Potts states that he has seen one of these voracious creatures kill and devour parts of fourteen small flies within a very brief space of time. This voracity and waste of animal food is very remarkable when we recollect that many Insects have such perfect powers of assimilation that during their whole period of growth they only consume a mass of food—and that vegetable—but little larger in size than the bulk they themselves attain. This fact is well known in the case of _Bruchus_, _Caryoborus_, and other seed-feeding Insects. Burmeister has stated good grounds for believing that some of the larger Mantidae do not confine themselves to Insect diet, but attack and devour small Vertebrates.[177] He has given a circumstantial account of a case at Buenos Ayres, where a small bird was secured by the wingless female of a large _Mantis_, which had commenced devouring its head when the observer took possession of the creature and its booty. Dubois states[178] that when a decapitated, but living, _Mantis_ was suspending itself to a roll of drapery by its four posterior legs, a person could detach with the fingers the left anterior leg (of the four) and the right posterior, or conversely the left posterior and right anterior, without the interference producing any action on the part of the creature; but if one of the other legs was also interfered with, which would necessarily have changed the position of the body, then immediately one of the two unoccupied legs was placed by the creature in a proper position to assure its stability. This reflex action altogether resembled in appearance a conscious action, and was as effectually performed.