The developmental morphology of the spermatophore of Gryllus bimaculatus

Examination of the early stages of spermatophore development revealed a flu id, almost invisible material, forming an apparently amorphous mass when re moved from the ejaculatory duct. Innovative techniques were devised to pres erve the material, as far as could be determined in its original state of o rganization. A clear sequence of events was then identified. Immediately fo llowing the reference point, which itself had proved difficult to identify, secretions from the accessory reproductive gland tubules produce the mater ial which becomes the primary capsule (the earliest identifiable stage of t he ampulla) and the beginnings of the attachment plate. At this very early stage, the forerunner of the sperm tube also appears. Following this, the p ressure bodies form and the sperm mass can be seen occupying a posterior po sition in the developing spermatophore, prior to moving into its final posi tion within the sperm sac itself. More attachment plate material is added a nd assimilated into the existing attachment plate material. The newly formi ng 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 ventr al lobes. The spermatophore is now ready for transfer to the female.