0000000000049702
AUTHOR
Werner Gnatzy
Die Feinstruktur der Sinneshaare auf den Cerci von Gryllus bimaculatus Deg. (Saltatoria, Gryllidae)
1. Zu Beginn der Hautungsvorgange werden bei den dicken und dunnen Borstenhaaren die Ciliarstrukturen sowie die sie umhullenden cuticularen Scheiden verlangert. 2. Vor der Ecdysis ragen die neu angelegten Haare in den Exuvialraum. Die cuticularen Scheiden und die Ciliarstrukturen durchqueren den Exuvialraum. Sie treten bei dicken und dunnen Borstenhaaren durch die Spitze der neu angelegten Haare und ziehen im Haarlumen bis zur Haarbasis. Auf diese Weise bleiben die Ciliarstrukturen der alten Haare bis zur Ecdysis mit den zugehorigen Sinneszellen verbunden. 3. Bei der Ecdysis reisen die cuticularen Scheiden an den Spitzen der neuen Borstenhaare ab. Dadurch entsteht hier ein Porus, uber den d…
Tormogen cell and receptor-lymph space in insect olfactory sensilla. Fine structure and histochemical properties in Calliphora.
(1) The basiconic sensilla on the antennae of Calliphora resemble other insect epidermal sensilla; one or several bipolar sense cells are surrounded by three non-neural cells. (2) The apical cell membrane of the tormogen cell (one of the three accessory cells) forms microvilli coated internally with particles. (3) In the (extracellular) outer receptor-lymph space hyaluronic acid can be demonstrated histochemically. (4) Demonstration of non-specific alkaline phosphatase, Mg2+-activated ATPase, and the presence of mitochondria in the apical part of the tormogen cell suggest active transport processes through these cells into the outer receptor-lymph space.
Arachnid oenocytes: ecdysone synthesis in the legs of harvestmen (Opilionidae).
Cells measuring up to 130 microns have been found in the proximal segments of the femora of all four pairs of walking legs in various species of harvestmen (Phalangium opilio, Leiobonum limbatum, Opilio parietinus, and Opilio ravennae). These cells exhibit all the fine-structural characteristics of insect oenocytes, in particular the conspicuous agranular endoplasmic reticulum. Radioimmunoassay after in vitro incubation of these cells has demonstrated the synthesis of alpha- and beta-ecdysone. These ecdysteroids have been found in the ovaries and tergites of the opisthosoma as well as in the oenocytes.
Cricket combined mechanoreceptors and kicking response
1. Only those filiform hairs on the cerci ofGryllus, which are coupled with campaniform sensilla, show a) a thickening of the hair shaft at the height of the upper ring lamella of their sockets and b) a thin cuticular membrane, which surrounds their sockets. While thefiliform hairs themselves are deflected either parallel to the long axis of the cerci or perpendicular to it, thesockets of the filiform hairs may be deflected preferentially in the proximal and distal direction. 2. Spike potentials can be recorded from the sensory cells of the filiform hairs as long as these are deflected in a weak air current, but not during permanent deflection in strong air streams when they touch the inner…
Struktur und Entwicklung des Integuments und der Oenocyten von Culex pipiens L. (Dipt.)
1. Struktur und Entwicklung des Integuments und der larvalen Oenocyten wahrend des Puppen- und pharaten Imaginalstadiums von Culex pipiens L. (Dipt.) werden beschrieben. 2. Auf- und Abbau der pupalen und die Anlage der imaginalen Cuticula verlaufen innerhalb enger zeitlicher Grenzen. 3. Beim Abbau der pupalen Endocuticula erscheint immer die Lamina der jeweils innersten Lamelle als „Hautungsmembran“. 4. Die Oenocyten sind durch ihr agranulares, tubulares endoplasmatisches Retikulum (ATER) und dessen Veranderungen charakterisiert. Die Struktur der Oenocyten gleicht der steroidproduzierender Wirbeltierzellen. 5. Das Aussehen der Oenocyten andert sich kurz nach der Puppenhautung hauptsachlich …
Cuticle: Formation, Moulting and Control
The relative rigidity of the arthropod exoskeleton makes it impossible for body size to increase continuously during the postembryonic development of these animals. Once they have hatched from the egg, they grow in steps, passing through a variable number of (larval) stages (Fig. 1 a). Apart from a few exceptions, there are between 3 and 10 such stages in the arachnids, 3–20 in the crustaceans, and 3–10 in the insects. In many cases a metamorphosis stage intervenes (some crustaceans; holometabolous insects) (Fig. 9b, c).
Die bauchblase von Nemurella picteti klapalek (Insecta, Plecoptera)
1. Die Bauchblase von Nemurella ist eine mediane Ausbuchtung des 9. Abdominalsternums. Sie kommt nur bei den ♂♂ vor. 2. Ventral und lateral sitzen nach den elektronenmikroskopischen Untersuchungen mechanorezeptorische Sinneshaare. 3. Zu jedem Haar gehoren eine bipolare Sinneszelle und jeweils drei Hullzellen. Unterhalb der Basis des Tubularkorpers ragt eine Verstarkungsrippe der cuticularen Scheide nach innen. Diese durfte dazu dienen, bei Reizung ein Ausweichen des Tubularkorpers nach unten zu verhindern. 4. Die Morphologie der Haare und ihre einheitliche Anordnung auf der Ventralseite in Langsrichtung der Bauchblase stimmen uberein mit der Beobachtung, das die Bauchblase zum Trommeln verw…
Development of the filiform hairs on the cerci of Gryllus bimaculatus Deg. (Saltatoria, Gryllidae)
The filiform hairs, mechanoreceptors of Gryllus, pass through six developmental stages during the last larval stage. The cytoplasm of their sense cells suggests intensive synthesis of protein for cellular metabolism and intercytoplasmic exchange of material via glial evaginations. Ultrahistochemical tests demonstrated acid phosphatase in the lysosomes as well as in components of the Golgi apparatus. There was no significant change in the appearance of the sense cell cytoplasm, indicating a maintained functional state also during molting. The new cuticular apparatus is formed after apolysis by the three enveloping cells. Formation of the replacement hairs is initiated by a cytoplasmic outgro…
Morphogenesis of mechanoreceptor and epidermal cells of crickets during the last instar, and its relation to molting-hormone level.
(1) The fine structure of the cercal campaniform sensilla and epidermal cells of Gryllus bimaculatus Deg. (Saltatoria, Gryllidae) was examined, and the ecdysteroid level was monitored throughout the last larval instar. (2) The epidermal cells show changes in shape, cytoplasmic inclusions and differentiation of the apical cell membrane, coupled to the phases of buildup and breakdown of the (cercus) cuticle. (3) The imaginal epicuticle of the epidermal cells begins to form later (by about approximately 6h) than that of the campaniform sensilla. (4) The campaniform sensilla were studied with respect to (a) the morphogenesis of the cuticular apparatus, (b) the inclusion of phenol oxidases in th…
The ultrastructure of the thread-hairs on the cerci of the cockroach Periplaneta americana L.: The intermoult phase
The structure of the thread-hairs on the cerci of the cockroach Periplaneta american during the intermoult phase has been investigated by scanning and transmission electron microscopy. The present study demonstrates that to each thread-hair belong one sensory cell, two glial cells, and three enveloping cells. The data indicate that: (a) the inner glial cells, which may have a trophic function, sends fingerlike processes into the cytoplasm of the senory cell body; (b) the internal enveloping cell forms the dendritic sheath; (c) the middle enveloping cell corresponds to the trichogen cell and the external enveloping cell to the tormogen cell; (d) the outer dendritic segment terminates in a ca…