Proprioception in Insects Iii. the Function of the Hair Sensilla at the Joints

LOWNE (1890) described an organ, which he called the "prosternal organ", from the extreme anterior part of the thorax of the blowfly. This seems to be the first mention in the literature of the peculiar concentrations of hair sensilla which are to be found near the joint surfaces in many parts of the insect body, and whose function presents an interesting problem. Lowne's figure of the prosternal organ of CaUiphora is reproduced in Text-fig. 1. It consists, in his words, of "a plate covered with long fine setae, beneath which