The morphologies of the cerebral ganglia (brains) three infraorders decapod crustaceans (Astacura-crayfish; Brachyura-crabs; Palinura-spiny lobsters) are described. A common nomenclature is proposed for homologous nerve roots, brain regions, tracts, commissures, neuropils, and cell body clusters.

The eyes of the crab Carcinus follow movement a horizontally rotating striped drum with constantly increasing lag. relative or slip speed is stimulus for eye, which increases its response over range speeds from 0.001°/s to 10.0°/s. gain in forward control system, i. e. ratio eye speed, can be as great 15. slowest effective very low, about sixth sun across sky. Whether seeing allowed move not, it will drive other if latter sees no contrasting objects. An also driven this way after section...

Abstract A survey of the morphology brains (cerebral ganglia) 13 species decapods shows that all have common areas neuropil are developed to differing degrees in different groups. The neuropils paired accessory lobes, however, appear evolved de novo Reptantia. Phylogenetic relationships within Reptantia suggest lobes were initially large but became reduced size during evolution brachyurans and anomalans. © 1993 Wiley‐Liss, Inc.

Abstract An atlas of neurons in the brain crayfish Cherax destructor that are immunoreactive to antibodies raised against serotonin has been compiled from whole mount preparations. Neuronal networks serotonin‐containing cells identified optic lobes and protocerebrum, deutocerebrum, tritocerebrum. The consistency whole‐mount technique allows 50 out a total about 100 be individually according their neuronal architecture or location cell somata axons. Apart six with axons oesophageal...

ABSTRACT The heads of resting flies will twitch to the side if haltere is deflected rapidly forwards. Head movements are always away from stimulated and do not occur up, down or backwards. anatomy action neck muscles described. Cobalt fills whole nerve show that sensory axons project neuropiles ipsi- contralateral pro- mesothoracic neuropiles, ipsilateral metathoracic cerebral ganglion. nerves prosternal organs central projections these end in prothoracic neuropile. Recordings motoneurones...

Ink injected into the blood system of crab reveals a rich capillary within all central ganglia. The capillaries link afferent vessels with efferent in such way that carry deep neuropile and take through synaptic areas out to surface efferents. ganglion sheath haemocoele. branches structured optic lobe are regularly spaced proliferation occurs at known areas. Capillaries diffuse brain not geometrically arranged. Blood flows initially regions thence past nerve somata. With exception retinula...

Abstract Background Several lineages within the Crustacea conquered land independently during evolution, thereby requiring physiological adaptations for a semi-terrestrial or even fully terrestrial lifestyle. Birgus latro Linnaeus, 1767, giant robber crab coconut (Anomura, Coenobitidae), is largest land-living arthropod and inhabits Indo-Pacific islands such as Christmas Island. B. has served model in numerous studies of aspects related to conquest by crustaceans. From an olfactory point...

ABSTRACT Irrigation of the statocysts crab Scylla serrata will activate oculomotor neurones associated with eye movements. An investigation central mechanism statocyst-induced nystagmus has been started description statocyst canals and a characterization sensory input from hair receptors in canals. The are shaped like two toroids joined at approximately right angles to one another. Direct observation isolated statoliths glass models them shows that when they rotated, fluid moves around...

Abstract Adult neurogenesis, the generation of new neurons from adult precursor cells, occurs in brains a phylogenetically diverse array animals. In higher (amniotic) vertebrates, these cells are glial that reside within specialized regions, known as neurogenic niches , elements which both support and regulate neurogenesis. The vivo identity location responsible for neurogenesis nonvertebrate taxa, however, remain largely unknown. Among invertebrates, has been particularly well characterized...

ABSTRACT The sensory axons of the thread hair receptors, free hook receptors and most statolith area crab statocyst all project to same dorsolateral part brain. Large which innervate some hairs surrounding a more ventral site, send branches across contralateral side central projections oculomotor neurones have characteristically open branch pattern their dendritic field corresponds closely with that hairs. There are no extending Intracellular responses from motor horizontal eye-movement...

The importance of empowering students to take charge their learning and become active participants in own education cannot be overemphasized. Developing student autonomy should a primary objective not only language but also any educational context. Reflecting critically on one's study the ability set goals are frequently lauded as cornerstones developing autonomy. This small-scale examines impact utilizing format for low proficiency reflect lessons, identify weaknesses, individual goals....

A small, medial heterolateral neuropil in the brain of crustaceans has long been regarded as central body crustacean brain. Its simplicity and absence clear layers within its have led to question homology with more complex that occupies an approximately equivalent position insects. We labelled neurons Australian freshwater crayfish Cherax destructor by extracellular application dextrans treating antibodies anti-CCAP, anti-locustatachykinin, anti-perisulfakinin, anti-proctolin,...

Abstract Freshwater crayfish have well‐developed olfactory systems with an array of receptors that project exclusively to areas in the brain are functionally specialized for processing odors. The accessory lobes large bilateral neuropil anatomically associated lobes. receive no primary afferents and do not contain endings motor efferents; thus, their role olfaction is still obscure. Intracellular dye filling interneurons deutocerebral commissure has shown they end bilaterally glomeruli...

Vibration of the rims open cells in a honeycomb, applied plane comb face, is transmitted across comb. Attenuation or amplification vibratory signal depends on its frequency and type In general, framed combs, both large small, strongly attenuate higher frequencies, whereas these are amplified small combs. The very poor transmission properties combs used commercial hives may explain bees' habit freeing an area from frame those areas for dancing. Extracellular electrical recordings leg honeybee...

Abstract One of the features common among olfactory systems for vertebrate and invertebrate species is division primary processing area into distinct clumps synaptic neuropil, called glomeruli . The appear to serve as functional units olfaction are location between chemosensory afferents second‐order neurons. Although found across all phyla, their numbers size be characteristic each species, giving rise speculation that there a relationship glomerular number function. It has been...

ABSTRACT Sensory hairs on the chelae of Australian freshwater crayfish Cherax destructor are grouped together into pits. Electrophysiological recordings from sensory axons isolated chelipeds show that maximally sensitive to water vibration frequencies between 150−300 Hz. The amplitude threshold is about 0·2 µm molecule oscillation.