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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Pine Engraver Beetles in the Low Elevation Sonoran Desert in Tucson

Warren, Peter, L., Quist, Tanya, M., Schuch, Ursula, K., Erickson, Chris, Celaya, Bob, Richardson, John 12 1900 (has links)
5 pp. / Pine engraver beetle refers to 11 species of insects (in the Ips genus) living in the inner bark of Arizona’s conifers that can cause rapid decline and tree death. Typically, the beetles are found at higher elevations (4200 feet to 9000 feet), but have recently been detected at about 2400 feet, in Tucson. The six-spined engraver (Ips calligraphus ponderosae) has been the only species detected, so far, in Tucson. This is the first time these native bark beetles have been found in non-native pines in the Sonoran Desert.
2

Electron microscopic studies of antennal sensilla in the ambrosia beetle Trypodendron lineatum (Olivier) (Scolytidae)

Moeck, Henry A. January 1967 (has links)
The antennae of the ambrosia beetle Trypodendron lineatum (Olivier) were examined with the light and electron microscopes to determine the types, distribution, and structure of sense organs found thereon. At least six types of sense organs were found, with an additional seventh cuticular structure, the hypodermal gland pore, which is thought to be non-sensory. The sensilla are sensilla chaetica, three types of sensillum tri-choideum, sensilla basiconica, and sensilla campaniformia. Distribution maps of the various sensillum types and the gland pores are presented, for one each of female and male left antenna. Sensilla chaetica, evenly distributed over all parts of the antennae, as well as the rest of the body, consist of a long thick-walled hair 20 to 140 micra long which articulates in a socket composed of a hair root, socket lining, and spongy cylinder. A single bipolar neuron terminates in a scolo-pale attached at one side of the hair base. Sensilla trichoidea, Type I, situated at the base of the scape and the base of the first funicular segment, are short thin hairs articulating in a socket. Their fine structure and innervation are not known. Sensilla trichoidea, Type II, found on the distal periphery of the club only, consist of sharply pointed smooth hairs 18 to 25 micra long, the hair wall being thin and perforated. The hair is solidly joined to the body cuticle. The sensillum has two bipolar neurons, the dendrites of which extend, with slight branching, to the distal limits of the hair lumen. No dendritic endings could be demonstrated at the hair perforations. Sensilla trichoidea, Type III, are evenly distributed over the distal half of the anterior club surface. The hair is 26 to 36 micra long, blunt-tipped, and curved in reverse, with the result that the hairs protrude at right angles to the club surface and beyond all other vestiture. The hair articulates in a socket, and has a double lumen. The dendrites of four to seven bipolar neurons extend through the eccentric small lumen to the hair tip, where, presumably, they are open to the air. Sensilla basiconica cover both club surfaces. At least two types exist, one group being short pegs 6 to 8 micra long, and another group being longer pegs or hairs llj to 18 micra long. The long sensilla basiconica have a thin perforated hair wall, the openings being slit-shaped (700Å by 100 to 200Å). The two nerve cells of this sensillura send two distal processes into the hair where subsequent repeated branching occurs. The relationship of the dendrite branches to the hair perforations is not clear. Sensilla campaniformia are found in small numbers on all parts of the antennae, as well as other parts of the body. They consist of a short thin canal leading from the outside, to a sub-surface dome 3 micra in diameter, in the centre of which lies the nerve ending similar in appearance to the scolo-pale and nerve of the sensillum chaeticum. Also, a cross section of the antennal nerve in the proximal portion of the scape revealed about 2100 axons. A count of the sensilla, corrected for the number of sense cells present per sensillum, gave expected axon numbers of 1845 and 1921 for female and male antennae, respectively, with Johnston's organ not accounted for. Since more axons than expected are present, axon fusion is considered unlikely. This sudy may serve as the basis for further electrophysiological work to determine the functions of the various sense organs. / Science, Faculty of / Zoology, Department of / Graduate
3

Biology of the asparagus beetle, Crioceris asparagi and Crioceris duodecim punctata, in western Massachusetts.

Capinera, John Lowell 01 January 1974 (has links) (PDF)
No description available.
4

The ecology of parental care in the saltmarsh beetle Bledius spectabilis

Wyatt, T. D. January 1983 (has links)
No description available.
5

The development and use of polymorphic DNA markers for use in population studies of Oryzaephilus surinamensis

Brown, Richard James January 1996 (has links)
No description available.
6

Feeding ecology of the carabid beetle Agonum dorsale in cerial crops

Griffiths, E. January 1983 (has links)
No description available.
7

The role of sex pheromones in the biology of Lasioderma serricorne (F) and Stegobium panceum (L) (Anobiidae : Coleoptera) and their potential for use in control procedures

Mhemed, A. J. January 1985 (has links)
No description available.
8

Resistance of some pea varieties to Callosobruchus maculatus F

Kannan, H. O. January 1984 (has links)
No description available.
9

The role of ladybird beetles in determining the abundance of cereal aphids

Wittaker, S. A. January 1987 (has links)
No description available.
10

Dracula vs. the Beetle : How Science is Used as a Rhetorical Tool to Bring the Monsters to Life

Thernlund, Martin January 2012 (has links)
This essay is a cultural/historical analysis of the role of science in the books Dracula by Bram Stoker and The Beetle by Richard Marsh. The aim is to investigate how science is used to lessen the amount of critical judgment the reader has to suspend while reading these two Gothic stories, as well as identifying what contexts science is part of. Initially, there is an introduction of the late nineteenth century Britain and the social and scientific events of that era, focusing on Darwinian ideologies, imperialism, and fear of degeneration. The conclusion reached is that science is used to inspire realism by increasing the feeling of authenticity, by erasing the boundaries of facts and beliefs with a juxtaposition of science and superstition, and by creating and upholding an uncanny effect.

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