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Topic: Ocelli


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In the News (Tue 17 Nov 09)

  
  Rosenzweig CHAPTER 5
Each of these ocelli is situated on a separate plane, with the 3 planes forming a 90 0 angle with one another and thus panoramically encircling the dome at the tip of the vertex.
The domeshaped corneas of the ocelli protrude outwards at an orientation of 90 0 to one another, with the distance between the two lateral ocelli being 330 µm while that between them and the median ocellus is 250 µm (Plate I, Figure B).
The lens of the ocelli is homologous to the comus of the ommatidium.
www.desc.med.vu.nl /Publications/Thesis/Rosenzweig/Rosenzweig_CHAPTER_5.htm   (9655 words)

  
 Psyche 55:113-130
The species of Perlesta are of moderate size ; they have three ocelli; the antennae have basal joints as long as broad, with many fine appressed hairs, each joint with one or more longer erect hairs (sense hairs).
It is yellowish to rufous, the ocelli faintly connected by a dark V-mark; legs are pale below with a brown streak above, the hind tibiae dark except near tip; hind femur fairly slender ; sides of ocellar triangle longer than base.
Brown marked with pale yellowish, ocelli joined by fairly broad, almost fl lines, a pale yellowish triangle within, laterally, each side of the front ocellus the dark is extended nearly to the margin of head.
www-swiss.ai.mit.edu /projects/psyche/55/55-113.html   (2401 words)

  
 Rosenzweig SUMMARY
The macroscopic structure of the ocelli and their spatial orientation enable the hornet, on the one hand, to determine the sun's direction during flight, and on the other hand they serve as a clock that lends hornets a temporal orientation.
Three ocelli are situated in the vertex plate which is shaped like a three-sided pyramid with a truncated tip.
As for the paraocellar crests, these actually function as gyroscopes and consist of a fluidfilled canal encased by a ciliary cells, the whole of which is rather analogous to the semicircular canal in the ear of vertebrates.
www.desc.med.vu.nl /Publications/Thesis/Rosenzweig/Rosenzweig_Summary.htm   (1186 words)

  
 Coral Reef Color, A Fish's-Eye View, learn more - National Geographic Magazine
Ocelli are light-sensitive regions in single-celled organisms or light-sensitive cells in animals.
These ocelli contain two different types of pigmented cells: some that shade and some that are light-sensitve.
This type of ocellus allows an animal to not only perceive the direction of a light source, but also, because of its multicellular nature, to detect an object moving past it—the shadow is detected by one cell after another as it moves across the ocellus.
www7.nationalgeographic.com /ngm/0505/feature5/learn.html   (547 words)

  
 How Fat Flies Finesse Flight | LiveScience
Then they beamed a pattern of flickering light on the fly's ocelli, similar to what it would see if it was rotating in the air.
Ocelli contain a single lens, and generate blurry images, as if looking at the world through a piece of tissue paper, Parsons explained.
But ocelli are much quicker at jetting signals to the fly's brain—a characteristic important when a fly is poised to possibly crash.
www.livescience.com /animals/061115_fly_roll.html   (491 words)

  
 Eyes
The length of the ocelli (from front to rear, called ocellar length), the distance between them (called inter-ocellar distance), the shape of the ocelli, and the distance from each ocellus to the compound eye on the same side of the head (called ocellar-ocular length), differentiate the three Gryllotalpa remaining species as follows:
In the European mole cricket the ocelli are nearly circular, and the the ocellar-ocular distance is greater than the ocellar length.
In the knife and oriental mole crickets, the ocelli are elliptical, and the ocellar-ocular distance is less than the ocellar length.
molecrickets.ifas.ufl.edu /mcri0037.htm   (153 words)

  
  Spartanburg SC | GoUpstate.com | Spartanburg Herald-Journal
In insects, ocelli are involved (along with compound eyes) in the horizon-detecting response, decreasing the latency between horizon changes and the insect's response.
Lateral ocelli have a mixture of rod cells and cone cells and are found on the sides of the head, one to six on each side.
Lateral ocelli are the only eyes of the larvae of several orders of insects (fleas, springtails, silverfish, and Strepsiptera).
www.goupstate.com /apps/pbcs.dll/section?category=NEWS&template=wiki&text=ocellus   (180 words)

  
  NationMaster - Encyclopedia: Ocellus   (Site not responding. Last check: )
Insects in particular have two types of ocelli: dorsal ocelli are light-sensitive organs on the dorsal surface or on the top of the head.
Insects with dorsal ocelli also have compound eyes, but lateral ocelli are the only eyes of the larvae of several orders of insects (fleas, springtails, silverfish, and Strepsiptera).
Lateral occlli have a mixture of rod cells and cone cells and are found on the sides of the head, one to six on each side.
www.nationmaster.com /encyclopedia/Ocellus   (599 words)

  
 ::The Moths of Borneo::   (Site not responding. Last check: )
The oval ocelli are flish above, reddish brown with white edging below, all ringed fl.
The ocelli are contained in a broad subdorsal stripe that runs from T1 to behind the ocellus then over dorsally to join with the opposite one.
The darker variants have the ocelli in a horseshoe thoracic marking also; on each abdominal segment there are four white or yellow spots dorsally.
www.arbec.com.my /moths/sphingidae/sphingidae_23_7.php   (323 words)

  
 Army News :: Top Stories :: Keep Clean
Ocelli are very important to airborne insects, using UV and green light to maintain straight and level flight.
Research has shown that dragonflies are far more reliant on their ocelli than other flying insects, partly because of their unique ability to create a focussed image rather than just shades of light.
The ocelli project grew from experiments first conducted at ANU in the 1970s and the current work on using vision for flight control began with funding from DSTO and the USAF in 1996.
www.defence.gov.au /news/armynews/editions/1059/topstories/story15.htm   (448 words)

  
 Insect Morphology and Anatomy (The Head)
The 'frons' = that area of the face below the top two 'ocelli' and above the 'frontoclypeal sulcus' (if and when this is visible) and in between the two 'frontogenal sulci', it supports the 'pharyngeal dilator' muscles and in immature forms it bears the lower two arms of the ecdysial cleavage lines.
The retinula cells are connected to axons at the base of the eye, it is these which carry the information collected by the lenses and converted into electrical impulses by the rhabdom to the brain, thus allowing the insect to see.
Ocelli are present in most insects to some degree, though as with all aspects of insect anatomy there is a great deal of variety in form and even in relative function.
www.earthlife.net /insects/anat-head.html   (2211 words)

  
 News | Gainesville.com | The Gainesville Sun | Gainesville, Fla.   (Site not responding. Last check: )
In smaller members of the Felidae family (such as the Leopard Cat), ocelli are white circular markings on the backs of the ears.
Lateral ocelli have a mixture of rod cells and cone cells and are found on the sides of the head, one to six on each side.
In insects, ocelli are involved (along with compound eyes) in the horizon-detecting response, decreasing the latency between horizon changes and the insect's response.
www.gainesville.com /apps/pbcs.dll/section?category=NEWS&template=wiki&text=ocellus   (252 words)

  
 Charles Darwin - Descent of Man - Chapter 14
In all species the ocelli on the wings and tail are either circular or oval, and consist of a beautiful, iridescent, greenish-blue or greenish-purple disc, with a fl border.
malaccense, the ocelli on the tail-coverts are, as we have seen, confluent; and these feathers are of unusual length, being two-thirds of the length of the tail-feathers, so that in both these respects they approach the tail-coverts of the peacock.
But even in the most perfect ball-and-socket ocelli a slight difference in the tints, though not in the shading, between the upper and lower parts of the ball can be perceived, as before noticed; and the line of separation is oblique, in the same direction as the bright coloured shades of the elliptic ornaments.
www.infidels.org /library/historical/charles_darwin/descent_of_man/chapter_14.html   (12179 words)

  
 Highbeam Encyclopedia - Search Results for ocellus
Sialidae (alderflies; subclass Pterygota, order Megaloptera) Family of insects which are similar to the Corydalidae, but are usually much smaller and lack ocelli.
They are flish-grey, resemble lacewings, and are found near ponds or streams, where their larvae develop.
nauplius eye A single median eye comprising three- or four-pigment cup ocelli, sometimes with a lens, probably enabling the organism to determine the direction of a source of light for orientation.
www.encyclopedia.com /SearchResults.aspx?Q=ocellus   (1150 words)

  
 Ocelli Information Page
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If Ocelli is attempting to crawl pages that don't exist, there may be outdated links on your website or an external website that need updating.
If you believe Ocelli is erroneously downloading content, please use the feedback form to notify us of a problem, including relevant URL and/or log information.
www.globalspec.com /Ocelli   (532 words)

  
 Aquarium Fish
The two ocelli on each side of the dorsal fin can change color depending on the lionfish's mood or social status.
The ocelli on the soft portion of the dorsal fin may serve a communicative function.
Thaler (2004) reports that the ocelli can take on a turquoise color and that the eyespot adopts this color when the fish is excited (whether by food, a mate or a competitor).
www.advancedaquarist.com /issues/nov2004/fish.htm   (1579 words)

  
 ocellus, ocelli - BugGuide.Net
The presence or number of ocelli is helpful in differentiating some groups, such as the families of Megaloptera.
Larval forms of holometabolous insects usually have simple eyes on the sides of the head corresponding to the location of the compound eyes in the adult, and these are not are not structurally homologous with ocelli.
Common entomological usage (1) is to call these "lateral ocelli", but sometimes they are called stemmata (singular stemma) (2).
bugguide.net /node/view/111296   (352 words)

  
 CHAPTER TWENTY SIX
Dorsal ocelli occur in larvae of hemimetabolous insects and in nearly all adults.
Light causes a sustained depolarization of the retinula cells, however, the biological roles of ocelli remain unknown.
In some orthopterans the ocelli are active in orientation to a light source.
entomology.unl.edu /ent801/vision.html   (1738 words)

  
 The Bumblebee Body, the eye
Ocelli look like shiny bumps, and resemble the 2 large "headlamp" type eyes easily seen in Lycosid spiders.
In the photograph above of a Bombus lapidarius male only two of the ocelli can be clearly seen as they reflect light.
Bombus hortorum queen compound eyes and ocelli, note the more elongated head typical of hortorum.
www.bumblebee.org /bodyEyehtm.htm   (288 words)

  
 [No title]
The Southeast Asian pheasant genus Polyplectron is comprised of six or seven species which are characterized by ocelli (ornamental eye-spots) in all but one species, though the size and distribution of ocelli vary among species.
The two least ornamented Polyplectron species, one of which completely lacks ocelli, have been considered to be the primitive members of the genus, implying that ocelli are a derived trait.
Maximum likelihood and maximum parsimony analyses of cytochrome b sequences suggest that the closest relatives of Polyplectron are probably the peafowl and the argus pheasants.
www.zoo.ufl.edu /rkimball/polyabs.html   (245 words)

  
 Ocelli@Everything2.com
Many adult insects, as well as some nymphs, have ocelli in addition to their compound eyes.
The three small ocelli lie in a triangle on top of the insect's head.
Ocelli are thought to function as 'horizon detectors' for control of roll and pitch movements while flying, and to register the cyclical, seasonal changes in light intensity that accompany diurnal behaviour.
everything2.com /index.pl?node=ocelli   (192 words)

  
 MySpace.com - Ocelli - Portland, Oregon - Other / Other / Other - www.myspace.com/ocelli
Ocelli (lance grider and kin) is a revolving ensemble that makes delicately woven ambient acoustic music.
Ocelli often plays while interpretive artists perform along side...such as ballerinas, a gothic belly dance troupe, a contortionist, a sexy crossdressing female exotic dancer, a butoh artist, a marrionette puppet troupe, and a video artist.
The new album, ‘Ocelli’ (Under the Underground), is comprised of vocals, guitar, violin, cello, piano, horns, bass, keyboards, harp, acoustic and electro beats.
www.myspace.com /ocelli   (703 words)

  
 * Ocelli - (Biology): Definition
Ocelli: Simple eyes on some adult and larval insects.
Typically there are three, which form an inverted triangle dorsally, the function of which is obscure.
Some of the simplest eyes, called ocelli, can be found in animals like snails, who cannot actually "see" in the common sense.
en.mimi.hu /biology/ocelli.html   (138 words)

  
 Caterpillar Anatomy- EnchantedLearning.com
Ocelli (also called stemmata) are small, simple eyes that can detect changes in light intensity, but cannot form an image.
Ocelli are composed of photoreceptors (light-sensitive cells) and pigments.
Ocelli are usually located in two clusters of six eyes on the sides of a larva's head.
www.enchantedlearning.com /subjects/butterfly/anatomy/Caterpillar.shtml   (1109 words)

  
 Untitled Document
Diagnosis: Medium to large leafhoppers; head weakly produced with transverse carina between ocelli, ocelli on anterior margin of crown near eyes, antennal ledge weak or absent; forewing venation complete, usually with supranumerary crossveins; hind femur macrosetal formula usually 2+2+1; male valve fused to pygofer, plates at least partially fused medially.
Diagnosis: Small, cylindrical leafhoppers; ocelli on face distant from eyes, lateral frontal sutures absent, clypellar suture incomplete; forewing with numerous supranumerary crossveins; hind femur macrosetal formula 2+1 or 2+0, tibia with macrosetae in row AV restricted to distal half.
Diagnosis: Medium-sized, usually green or brown leafhoppers; head with ocelli distant from eyes, lateral frontal sutures not extended to ocelli; forewing macropterous, often setose; hind wing veins R4+5 and M1+2 usually confluent; male with sternum VIII enlarged and largely concealing plates, plates ligulate; female second valvulae usually with 2-3 widely spaced dorsal teeth.
www.inhs.uiuc.edu /~dietrich/sfguide.html   (1699 words)

  
 Bee Anatomy
Simple eyes, called ocelli, are found near the front and top of the head.
Ocelli register intensity, wavelength, and duration of light.
At dusk the ocelli estimate extent of approaching darkness, causing the bees to return to their hives.
www.uni.uiuc.edu /~stone2/Bee_anatomy.html   (717 words)

  
 Grey Peacock-Pheasant, Polyplectron bicalcaratum
Males have metallic bluish-green ocelli on the wings and mantle.
Each tail feather is marked with two large metallic green, with a tint of purple, ocelli.
The ocelli is not near as bright or large as well.
www.gbwf.org /pheasants/grey_peacock.html   (672 words)

  
 Ocelli
Nonetheless ocelli -- eyespots on the wings of butterflies and moths -- exemplify the work of fiction in an ecology of predators.
Rather than crises of representation, such markings produce movement and flight; they are an aspect of the Umwelt of organisms, as much an element of their locomotion and fitness as wings themselves -- they are techniques of flight that require no movement; movement is provoked in the other.
Instead, Dick’s ocelli, in their hallucinogenic provocations, enable the breakdown of our space/time matrices of linear time, an allopoetic breakdown that, for Dick, more fully prepares us for the actuality of a dislocating alliance.
www.personal.psu.edu /faculty/r/m/rmd12/ocelli.html   (4410 words)

  
 Interactive Fly, Drosophila
Left and right ocelli are derived from the left and right eye-antennal imaginal discs, while the median ocellus derives equally from both discs once they fuse together after puparium formation.
The axons from four separate transient populations of about 50 ocellar pioneer neurons (one from each lateral ocelli, and one each from right and left rudiments of the median ocellus) project from the pupal ocelli to the brain.
At a later pupal stage, the adult ocellar photoreceptors are born and differentiate concentrically outside the cluster of pioneers.
www.sdbonline.org /fly/newgene/laminna1.htm   (1133 words)

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