Camera lucida

The most commonly employed method for measuring bacteria is by means of an ocular micrometer. Measurements may also be made by using a camera-lucida attachment and drawing oculars, or by projecting the real image on a screen and measuring the bacteria. 

FIGURE 56-7 Repeated exposure to amphetamine or cocaine increases spine density and the number of branched spines in medium spiny neurons, the major cell type of the nucleus accumbens. Left camera lucida drawings of representative dendritic segments. Rats received 20 injections of saline (S), amphetamine (A) or cocaine (C) over 4 weeks and were then left undisturbed for about 1 month prior to analysis. Adapted from Robinson, T. E. and Kolb, B., Eur. ]. Neurosci. 11 1598-1604, 1999. 

The engraving exhihlts the principal animal and vegetal productions contained In the Thames water at Richmond, drawn with the camera lucida, and mag nified two hundred and twenty diameters. 

For many types of granular material the camera lucida has been found useful. This device consists of a prism arrangement on the eyepiece of a microscope so that the particles are projected downward to one side... 

Figure 4. Octopamine content of various tissues associated with the oviducts of Locusta migratoria. Shaded areas of oviducts illustrate the approximate sites which were assayed. Inset upper right depicts a camera lucida drawing of one of the dorsal unpaired median neurons (DUMOV) injected with Lucifer yellow. Scale bar 50 jam. Data from reference 9.

Fig. 74. Camera lucida drawing of serotonin immunostaining in Lobule X of the cerebellum of the rat (A) and the paramedian lobule (PML) (B). Sagittal sections. Grl = granular layer ML = molecular layer WM = white matter. Calibration bar = 200 fim. Bishop and Ho (1985).

Fig. 79. Photomicrograph of camera lucida drawing (inset) of anterogradely labelled axons and terminal boutons in the crus I ansiform lobule of rat cerebellum after cholera toxin (b fragment) injection into the contralateral ventral tegmental area. Arrows point to rosettes characteristic of mossy fiber endings in the granular layer (G). P, Purkinje cell layer WM, white matter. Scale bar = 40 ixm. Ikai et al. (1992).

Fig. 3. The axon morphology of the SETi motoneuron in the grasshopper embryo at 48% of embyrogenesis. The branches indicated by arrows are inappropriate branches, never observed in animals older than 58% of embryogenesis. Camera lucida drawing of a LY intracellular fill. Scale bar= 100 m (reproduced with permission from Myers et al., 1990).

Fig. 5. The axon morphology of the motoneuron FETi in the grasshopper embryo following ablation of its target limb bud prior to axonogenesis. These two examples illustrate the variability observed in the pattern of axon branching from this motoneuron. Camera lucida drawings of intracellular LY fills. Scale bar = 50//m, 75% embryo (reproduced with permission from Whitington and Seifert, 1984).

Fig. 6. The role of peripheral neuron somata in sensory axon guidance in the wing disc of Drosophila. (A-C) The sequence of axon growth from sensory neurons in the wing disc. (A) 6 h after pupariation (AP). (B)12 h AP. (C) 30 h AP. Axons from distal neurons contact the somata of more proximal neurons (e.g. L3-2 axon contacts L3-v soma) en route to the base of the wing disc. For example, arrow in (B) indicates where the axon of L3-2 contacts the L3-v soma. Camera lucida drawings of embryos stained using anti-HRP immunohistochemistry. Scale bars (A) 85/

Fig. 7. RP axons in the Drosophila embryo are guided into the connective by contact with their contralateral, homologous soma. During normal development, the axons of the RPl (A) and RP3 (B) motoneurons wrap around the soma of their contralateral homologue after crossing the midline and prior to entering the longitudinal connective, ac, anterior commissure pc, posterior commissure. Scale bar = 5/

Fig. 10. Effect of ablation of the Cxi neurons on axon growth from the Til neurons in the grasshopper embryo. (A) Operated leg in which the Cxi neurons had been killed at the onset of Til neuron axonogenesis and the embryo allowed to develop further in culture medium. Asterisk indicates debris of Cxi cells. The Til axons possess multiple abnormal branches (arrowheads). (B) Contralateral control limb for (A) The Til axons take a normal pathway to the CNS. (C) Operated limb bud. The Til axons project straight ahead (arrowhead) towards efferent axons from the CNS, rather than turning posteriorly towards the Cxi cell site. (D) Contralateral control limb bud for (C), showing a normal Ti 1 trajectory. Camera lucida drawings from anti-HRP immunohistochemistry preparations. Scale bar = 100 /tm (reproduced with permission from Nature 304, (1983) Macmillan Magazines Limited).

Fig. 15. The growth cone of the motoneuron SETi in the grasshopper embryo extends a planar array of filopodia when encountering the basal lamina. Virtually all of the filopodia of this neuron, which is drawn from the dorsal perspective, lie in a single plane, just beneath the basal lamina. Camera lucida drawing from a neuron intracellularly injected with LY. Scale bar = 25, m (reproduced with permission from Whitington, 1989, Company of Biologists, Ltd.).

B. Hall, Forty Etchings, from Sketches Made with the Camera Lucida in North America in 1827 and 1828, CadeU Co., Edinburgh (1829), memorandum. 

In order to study the effect that T could have on the structure of the dendritic arborization of pyramidal neurons, a total of 18 such neurons, chosen at random from layer III of the visual area of the C.C. of 10 control Wistar rats 80 days old, and an equal number of neurons of the same layer of the C.C. of 10 rats of the same age, T when they were 10 days old, were drawn using a camera lucida with a total magnification of 500X. 

The weathered material of Dialipina collected in 1995 was prepared as negatives and the casts (Latex peels) were studied. The material collected in 1997 contains complete specimens, which could be prepared with acetic acid. The material, dusted with NH Cl, was drawn with a camera lucida attached to a Wild M8Z microscope, and photographed. 

The Golgi Atlas presents a series of camera lucida drawings of the entire telencephalon and upper brain stem of the young postnatal mouse in 24 transverse, 11 sagittal and 15 horizontal planes. The drawings were prepared from selected brains stained in toto with the Golgi method, that have been serially sectioned in the three orthogonal planes. 

Fig. 7. Camera lucida tracings of Purkinje cells of cerebellum on postnatal days 5 (p5), 10 (plO), and 20 (p20) of control group and methyl mercuiy-treated group. Rapid Golgi preparation. MeHg was injected into mothers on day 16 of gestation, 15 mg/kg).

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