A Morphological Study of the Respiratory Horns Associated with the Puparia of Some Diptera, Especially Ophyra Anescens (Wied.)1

Abstract

This study concerns the respiratory horns of three species of Diptera. “Respiratory horns” is the common name given to a pair of pronglike structures which occur on the dorsolateral aspect of the cephalic half of a number of pupae and puparia of Diptera, especially among Cyclorrhapha. De Meijere (1902) made the first systematic attempt to describe the structure of the respiratory horns in various families of Diptera, drawing information both from his own observation and from the scattered descriptions in the literature. Many interesting examples of respiratory horns in pupae have been described and figured in several papers dealing with the morphology of larvae and pupae of Diptera. The figures in these papers give a clear idea of the great variations in size, shape and structure of these horns, often described as prothoracic horns, trumpets, spiracles, siphons or gills. Their size varies from short, sessile and hardly perceptible to long and distinctly prominent projections in some pupae.