The developmental morphology of the spermatophore of Gryllus bimaculatus

Abstract

Summary Examination of the early stages of spermatophore development revealed a fluid, almost invisible material, forming an apparently amorphous mass when removed from the ejaculatory duct. Innovative techniques were devised to preserve the material, as far as could be determined in its original state of organization. A clear sequence of events was then identified. Immediately following the reference point, which itself had proved difficult to identify, secretions from the accessory reproductive gland tubules produce the material which becomes the primary capsule (the earliest identifiable stage of the ampulla) and the beginnings of the attachment plate. At this very early stage, the forerunner of the sperm tube also appears. Following this, the pressure bodies form and the sperm mass can be seen occupying a posterior position in the developing spermatophore, prior to moving into its final position within the sperm sac itself. More attachment plate material is added and assimilated into the existing attachment plate material. The newly forming spermatophore is protruded onto the subgenital plate, and the attachment plate material and sperm tube are pushed into the dorsal cavity. The sperm tube extends and hardens, as does the attachment plate, which itself takes the shape of its mould. As the ampulla hardens, it is moulded by the ventral lobes. The spermatophore is now ready for transfer to the female.