Economic Zoology: An Introductory Text-book in Zoology, with Special Reference to Its Applications in Agriculture, Commerce, and Medicine |
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Economic Zoology: An Introductory Text-Book in Zoology, with Special ... Herbert Osborn No preview available - 2018 |
Common terms and phrases
abdomen adapted adult alimentary canal alimentary tract Amphioxus anal opening animals antennæ aperture appendages aquatic artery attached birds blood body branchial burrows carapace cavity cells cephalothorax character colony common compound eyes connected destructive Diagram distinct distribution division domestic dorsal duct ectoderm eggs elongated endoderm esophagus extended external eyes feed female fishes forms ganglia gills glands habit hatch head host inches includes individuals insects intestine large number larva larvæ layers legs located male mammals maxilla minute mollusks muscles nephridia nerve cord nervous system nests notochord occur Order organs ovary oviduct pair parasitic Parker and Haswell pharynx plants plates portion posterior primitive Protozoa pupa region reproductive respiration segments sheep shell side slender specialized species spiracles stage stomach structure surface tail tapeworm tentacles thorax tion tissues U. S. Dep usually vas deferens vein ventral ventricle vertebral column vertebrates vessels wings
Popular passages
Page 286 - The larvae are fleshy grubs or maggots, or slender worms, adapted in the different families to widely different conditions of existence, but in nearly all cases requiring some degree of moisture. In this respect they range all the way from the entirely aquatic mosquito larvae to the forms which mature in comparatively dry situations in earth or even upon plants. The pupae are in some cases formed by the simple contraction and hardening of the larval skin and in disclosing the imago may either split...
Page 287 - The pupae are also active and move about in the water during their brief existence in this form, rising to the surface for air, which is taken through a spiracle near the head When the insect is ready to emerge the pupa rests at the surface with the dorsal face slightly out of the water, the case splits and the mosquito draws out first the front legs FIG.
Page 286 - ... however, to do this makes other methods still preferable. Doubtless some improvements in details of application may much facilitate treatment in this manner, and we would call attention to the subject discussed more fully in Chapter VII. CHAPTER II. DIPTERA. Mosquitoes, Gnats, Flies, and Ticks. The insects of this group are readily distinguished by their having only one pair of wings, the second pair, common to other insects, being represented by a pair of rudiments or modified structures called...
Page 83 - Davaine; /, daughter cyst with one endogenous and one exogenous granddaughter cyst; v, e, formation of endogenous daughter cysts, after Naunyn and Leuckart, — -y, at the expense of a head; z, from a brood capsule; evag., constricted portion of the mother cyst.
Page 474 - Era Permian Period Carboniferous Period Devonian Period Silurian Period Ordovician Period Cambrian Period Precambrian Time Table 2.
Page 301 - A, Head of Queen, magnified ten times, showing Smaller Compound Eyes at sides, and three Ocelli on Vertex of Head— n, Jaw Notch. B, Head of Drone, magnified ten times, showing Larger Compound Eyes at sides, with three Ocelli between— n, Jaw Notch. C, Section through Compound Eye — h, Hairs passing through Cornea ; c, Faceted Cornea ; cr, Crystalline Cone ; p, Pigment Cells ; on, Optic Nerve ; /t, //, Ganglia.
Page 319 - A. brain and cerebral nerves of a young specimen; B, transverse section through neuropore ; C, behind cerebral ventricle ; D. through dorsal dilatation. ch.
Page 222 - ... as man. The migrations between these hosts, which are evidently an essential part of its existence, may be stated in brief to be the discharge of numerous eggs in the nasal cavitites of the dog or other host, which, in sneezing or coughing, spreads them over vegetation that later is taken as food by some herbivorous animal, and following this ingestion the embryos escape into the glands and viscera of the new host, occupying especially the mesenteric glands, liver, etc., whe-e they remain in...
Page 214 - ... hen on the nest hatches them by the millions. Every crack and crevice contains them. They come out on the roost at night, like bed-bugs, and prey on the birds. The dust bath is considered of use in checking this pest, but where there is a general infestation, I believe the best plan will be found to clear the house, then spray well with kerosene or kerosene emulsion, taking pains to reach the cracks; thoroughly- drench the roosts with hot water or kerosene, benzine, or gasoline, whitewash the...
Page 17 - LOBOSA) as seen from above, /, shell; 2, pseudopodia ; 3, edge of opening into shell; 4, thread attaching animal to interior of shell; 5, nucleus; 6, food vacuole ; 7, gas vacuole.