Biological Notes on an Old Farm: Common Things As Seen By a

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Skeletal elements, choanocytes, and other cells are imbedded in a gelatinous matrix called mesohyl or mesoglea. The comparative biology of American black widow spiders. Lawrence (eds.), Echinoderm Studies, Vol. 1. There are five coelomocytes in males and six in adult hermaphrodites of C. elegans [ 39 ]. In deserts and in the tropics, ants replace earthworms as the most abundant earth movers (ants are nearly as important as earth- worms even in temperate regions).

Neuroptera (Including Megaloptera) (Encyclopedia of South

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They also release molecules that manipulate the host’s immune system. There are three categories of adhesive suckers upon which ordinal and subordinal classification of ces- todes is partially based. Each choanocyte chamber opens to the atrium by a wide aperture called an apopyle. A state Senate committee was considering a bill Tuesday that would allow homeowners to take some steps to stabilize the cliffs without worrying about the beetles.

Earwigs of California (Bulletin of the California Insect

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The oligochaetes (earthworms and their kin) lack any unique defining synapomorphies; hence they are de- picted as the hypothetical direct ancestors of the hiru- dinidans (leeches and their kin)—that is, leeches proba- bly evolved from an oligochaetous ancestor. The host tissue often forms a cyst around the glochidium. A Student’s Guide to the Seashore, 2nd Ed. SUBCLASS EUECHINOIDEA: Sea urchins, heart urchins, lamp urchins, sea biscuits, sand dollars.

THE INSECTS: STRUCTURE AND FUNCTION (BIOLOGICAL SCIENCE

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As the mesoderm con- tributes to various organs and tissues, the coelomic spaces merge with the small blastocoel to produce the hemocoelic space. In many plant eaters, the labrum bears a notch or cleft in which a stem or leaf edge may be lodged while being eaten. Proterozoic seas might have been oxic near the surface, but anoxic in deep waters and on the bottom. Please contact Robert Guralnick or collections manager Gene Hall with any questions about the collection's specimens and database.

A Revision of the Indo-West Pacific Fossil and Recent

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These animals show various degrees of compaction and fusion of the body somites and the as- sociated nervous system components while still con- forming to the basic annelid–arthropod plan. On the origin and phylogeny of the coelenterates. Many, how- ever, are free-living predators, and some are scavengers. This expanded volume covers sponges, sea anemones, hydroids, jellyfish, flatworms, polychaetes, amphipods, crabs, insects, snails, clams, chitons, and scores of other important groups.

Ecology and Classification of North American Freshwater

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Evolution within the Metazoa The first metazoans. The end of the Cretaceous was marked by the Cre- taceous–Tertiary mass extinction, in which an estimated 50 percent of Earth’s species were lost, including the di- nosaurs and all of the sea’s rich Mesozoic ammonite di- versity. Much of his early work was conducted aboard oceanographic cruises or through SCUBA diving. Video recorders allow zoologists to make visual tapes of animal behavior on both land and water. Distribution of Saturniidae of western North America.

The Colony

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Taken together, these and other poriferan at- tributes suggest that the sponges arose very early in metazoan cladogenesis. UNCORRECTED PAGE PROOFS common genital opening, and in a few the male atrium opens just inside the mouth. FAMILY NAIDIDAE: Many freshwater species; some live in marine or brackish water; some parasitic forms; some build tubes; several species bear an elongate prostomial proboscis; a few possess gills; al- most all reproduce asexually, but most possess go- nads at some stage of development; these fully aquatic oligochaetes occur worldwide. (e.g., Bran- chiodrilus, Dero, Ripistes, Slavina, Stylaria) FAMILY LUMBRICIDAE: Includes the common ter- restrial earthworms; often relatively large; with well developed and complex reproductive systems; most are direct deposit feeders. (e.g., Allolobophora, Di- porodrilus, Eisenia, Lumbricus) Figure 13.4 Representative oligochaetes. (A) An earth- worm (family Lumbricidae). (B) Branchiura (family Tubi- ficidae), a somewhat heteronomous oligochaete with digiti- form posterior gills. (C) The tube-dwelling, freshwater tubifi- cid, Tubifex.

Diapause in Aquatic Invertebrates: Theory and Human Use

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Prior to 1990, analyses of invertebrate phy- logeny were generally presented as narrative scenarios. Mus., Suppl 13 (1/2): 1–866. [A benchmark compilation by one of the world’s foremost, and most colorful, carcinologists.] Barnard, J. PHYLUM GNATHOSTOMULIDA ORDER FILOSPERMOIDEA: Body usually very elongate, with slender rostrum; males without penis; sperm filiform; females without vagina. (e.g., Haplognathia, Pterognathia) ORDER BURSOVAGINOIDEA: Body usually not extremely elongate relative to width; without slender rostrum; males with penis; sperm not filiform; females with bursa and usually a vagina. (e.g., Austrognatharia, Gnathostomula) Body Wall, Support, and Locomotion Each outer epithelial cell bears a single cilium by which the animal moves in a gliding motion.

Studies on Malacostraca: Lipke Bijdeley Holthuis Memorial

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Volumes 2-5 (Grasshoppers: Acridomorpha). Ivanova, Effect of habitat and motor activity of molluscs on fatty acid composition of triglycerides and phospholipids, Journal of Evolutionary Biochemistry and Physiology, 2009, 45, 1, 51 R. In certain areas of extreme environmental conditions, marine tardigrades may undergo an annual cycle of cy- clomorphosis (rather than the cryptobiosis typical of terrestrial and freshwater forms). During this swim- ming phase the larvae of at least some species can change shape rapidly from elongate to ovoid to flat.

Crustacea Guide Of The World

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A common plan for dorsoventral patterning in bilateria. These are smaller files that will download faster. The Branchiobdellida: Epizootic annelids. Their skeletons  are made mostly of cartilage and not actual bone, being of a more  ancient classification of fish in evol…utionary terms.    Whether something is cute or not is subjective, however sharks  aren't exactly an animal that have the head/body porportions  similar to what humans usually see as cute, they don't look  neotonous (like babies).