RESUMO
Studies have been made on the structure of neuropiles and visual pathoways in the brain of the fly E. tenax L. (Diptera, Syrphidae). The retina is projected on laminar structures in the visual ganglia only; other protocerebrum neuropiles lack this projection. All the comissures connecting contralateral visual ganglia, consist of several hundreds of fibers, whereas the binocular zone of both eyes includes more than 4,000 ommatidia. Neither the visual ganglia, nor other protocerebrum neuropiles may serve as a substrate for topographic imposition of projections of the corresponding parts in both retines. The mechanism of binocular interaction in insects presumably differs from that in mammals (primates, carnovores).
Assuntos
Dípteros/fisiologia , Fenômenos Fisiológicos do Sistema Nervoso , Visão Ocular , Animais , Gânglios/fisiologia , Sistema Nervoso/anatomia & histologiaRESUMO
The insects selected for measurements-- predators and anthophiles -- presumably possessed the ability of binocular estimation of distances. The margins of visual field and of the binocular zone in a compound eye could be traced by means of ophthalmological methods, such as observation of a pseudopupil or of a glow of ommatidia lit from inside. Predators as well as males of flies and drones, which intercept a point target against the sky, have the smallest binocular zone. They could not discover the distance to a target by binocular vision. Anthophiles have a broad binocular "window" pointing in antero--ventral direction; their binocular zone encloses 20--25% of facets. Predators hunting amidst the vegetation have the largest binocular zone (30--75%). The binocular zone of the eyes in the insects of large and middle size consists of 2--9 thousand of ommatidia.