Fritz Haas curator The majority of endangered species in the U. The area of geographic strength in our freshwater bivalves is North America. Most historical marine material, approximately 90, lots, was received as part of formed collections or as voucher material. There is a good synoptic representation of the extant marine mollusks and a growing, taxonomically diverse collection of small-shelled "micro" mollusks. Geographic coverage is world-wide with strengths in Florida and the Caribbean. The collection contains considerable historically important marine material acquired in several major private collections 48 KB and material that is resulting from field work by curators.
Geographic Coverage. The marine mollusk collection has a worldwide coverage with particular strengths in Florida and the Caribbean, as well as in deep-sea and hot-vent environments. Within the terrestrial and freshwater molluscan collections there is strong representation from the Nearctic, Neotropical, Pacific Island, Australian and European regions. Through the field collections of former Curator A.
Solem, The Field Museum's holdings of land snails from the Pacific Islands and especially from Australia are among the most comprehensive in the world. Acquisition of several important collections, in particular the Leslie Hubricht Collection in , made this among the world's premier collections of terrestrial mollusks. Among the unique components of the Invertebrate Collection are specimens collected by submersibles at sea floor hydrothermal vents in the east Pacific Ocean.
Fluid-Preserved Specimens. Our growing collection of alcohol-preserved specimens currently comprises approximately 30, series and 5, taxa. There are strong holdings of terrestrial snails from North America, Australia, Pacific Islands and Europe, as well as marine mollusks from the tropical West Atlantic Ocean and from deep-sea habitats in the Northeast Pacific Ocean. Type Collection. The molluscan type collection contains representatives of several thousand nominal taxa. Type designations by just three Field Museum-associated authors, Haas, Hubricht and Solem, account for over species.
Published by Springer About this Item: Springer, Condition: Good. First Printing. Former Library book. Shows some signs of wear, and may have some markings on the inside. Seller Inventory GRP More information about this seller Contact this seller 2. Connecting readers with great books since Customer service is our top priority!. More information about this seller Contact this seller 3.
Almost like new. This is a brown hardcover without dust jacket, , published by Plenum Press, volume 3 in the series, pp. As new except name inside front cover. You can expect professional service and individual attention to your order, daily shipments, and sturdy packaging. Seller Inventory Baculites , a genus of straight-shelled cephalopods, was particularly abundant in the Cretaceous seas. Note the elaborate suture patterns in the fossil specimen below. Common fossils in the Cretaceous rocks, the cephalopods were major victims along with the gastropod group the rudistids of the terminal Cretaceous extinction event.
Squid, octopus, and the chambered nautilus are the remnants of this once flourishing group of molluscs. Top left: Eubranoceras sp. The specimen is 2. Top right: Baculites was a straight-shelled cephalopod, about two feet in length, that presumably scavenged the bottom in search of food. Bottom: Baculites. Notice the extremely intricate suturing between septa. The phylum Annelida contains segmented worms such a the earthworm, shown in Figure The development of segmented bodies allowed the formation of specialized functions in different segments.
Annelids have an enlarged coelom to accommodate more complex internal organs.
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The well-developed, fluid-filled coelom and the tough integument act as a hydrostatic skeleton. There are about 12, marine, freshwater, and terrestrial species usually divided into three taxonomic classes. Similarities of larval forms to Mollusks suggest annelids share an common ancestral group. Annelids have a closed circulatory system with blood vessels running the length of the body and branching into every segment. Closed circulatory systems are more efficient than open ones for moving materials within a body. The annelid nervous system consists of a brain connected to a ventral solid nerve cord, with a ganglion in each segment.
Annelids have a complete digestive system that include a pharynx, stomach, intestine, and accessory glands. Excretory nephridia in each segment collect waste material from coelom and excrete it through the body wall. Top: anatomy of an earthworm. Lower: cross-section through the earthworm body. Note the presence of a coelom. Images from Purves et al. Most annelids belonging to the taxonomic class Polychaeta are marine and possess parapodia and setae. Parapodia are paddlelike appendages used in swimming that also serve as respiratory organs. Setae are bristles, attached to parapodia, that help anchor polychaetes to their substratum and also help them move.
Clam worms, such as Nereis, are active predators. Many have well-developed cephalization, with a head having well-developed jaws, eyes, and other sense organs.
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Sedentary filter feeders possess tentacles with cilia to create water currents and to select food particles. Only during breeding do polychaetes have reproductive organs. Polychaet zygotes develop into a type of larva similar to that produced by marine clams. The class Oligochaeta includes earthworms, that tend to have their few setae protruding in clusters directly from their body. Earthworms have poorly developed heads or parapodia. Locomotion is by coordinated movement of the body muscles and assistance of their setae.
When longitudinal muscles contract, segments bulge and setae protrude and anchor into the soil. Circular muscles contract, causing the worm to lengthen, setae are withdrawn and the segment moves forward. Earthworms reside in moist soil where a moist body wall facilitates gas exchange. Earthworms are scavengers that extract organic remains from the soil they eat.
A muscular pharynx draws food into the mouth. Ingested food is stored in a crop and ground up in a muscular gizzard.
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The dorsal surface of the intestine is expanded into a typhlosole that allows more surface area for digestion. External segments correspond to internal septa walls separating each body segment. The earthworm excretory system has coiled nephridia tubules in each segment with two openings: one is a ciliated funnel that collects coelomic fluid, and the other is an exit in the body wall.
Between the two openings, the coiled nephridia tubule allows removal of waste materials from blood vessels. Red blood is moved anteriorly by a dorsal blood vessel and pumped by five pairs of hearts sometimes referred to as aortic arches to a ventral vessel. Earthworms are hermaphroditic, having both testes with seminal vesicles, and ovaries with seminal receptacles. Mating involves the worms lying parallel to each other facing opposite directions and exchanging sperm.
Each worm possesses a clitellum that then secretes a mucus, protecting sperm and eggs from drying out. Embryonic development lacks a larval stage. The class Hirudinea includes leeches. Most are freshwater, but a few are marine or terrestrial. Each body ring has several transverse grooves. Leeches possess a small anterior sucker around the mouth and a larger posterior sucker. Although some are free-living predators, most are fluid feeders.
Bloodsuckers keep blood from coagulating by hirudin, an anticoagulant in their saliva. Leeches were commonly used in early medicine to "bleed" the patient. The phylum Arthropoda contains animals with segmented appendages on their body segments. Arthropods occupy every habitat, and are in many respects the most successful animal group on Earth.
There are conservatively over 1 million species of living arthropods. Biologist E. Wilson estimates there are 10 million species, 9 million of which are arthropods. Certain groups of arthropds have extremely complete fossil records. The arthropod body consists of three major collections or zones of body segments:.
Due to their great diversity of appendages, lifestyles, and other features, arthropods are usually separated into several subphylums. The subphylum Chelicerata includes spiders, scorpions, ticks, mites, horseshoe crabs, etc. The first pair of appendages are chelicerae, second pair are pedipalps, and the next four pairs are walking legs. Chelicerae are appendages that function as feeding organs. Pedipalps are feeding or sensory in function; although in scorpions, they are large pincers. All appendages attach to a cephalothorax, a fusion of the head and thoracic regions.
The head lacks antennae, mandibles, or maxillae appendages. The class Merostomata contains the extinct "sea scorpions" or eurypterids and the extant living horseshoe crabs. Eurypterids are extinct, but were important elements of faunas million years ago during the Paleozoic Era.
Some were huge, reaching a length of over 10 feet. Some eurypterids may have been amphibious, emerging onto land for at least part of their life. Horseshoe crabs are an ancient group consisting today of only 5 species. Members of this class have a large shield that covers the cephalothorax. The compound eyes are reduced.
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The second pair of appendages, the pedipalps, resemble walking legs. They have a long, spike-like appendage called a telson that projects from the rear of their bodies. Respiration is via book gills precursors to book lungs? The horseshoe crab genus Limulus is a familiar sight along the east coast of North America. The anterior shield is a horseshoe-shaped carapace with two compound eyes. The long, unsegmented telson projects to the rear.
They possess book gills that resemble the pages in a book. Limulus is considered a living fossil due to its great similarity to fossil forms from the Paleozoic Era. The class Arachnida includes over 60, described species and most likely a very large number of as yet undescribed ones of spiders around 35, species , mites and ticks 25, species , scorpions species , and other forms. Nearly all arachnids are terrestrial. Arachnids have a cephalothorax covered with a carapace-like shield. The abdomen may be segmented or unsegmented. Appendages on the abdomen are absent or modified, for example forming the spinnerets of spiders.
Respiration is via tracheae or book lungs. Scorpions are arachnids. They are the oldest terrestrial arthropods known from fossils. All scorpions are nocturnal and spend most of the day hidden under a log or rock. Their pedipalps are large pincerlike appendages, and their abdomen ends in a stinger containing venom. Ticks, shown in Figure 17, are parasites that suck blood and sometimes transmit diseases.
Chiggers are larvae of certain mites and feed on the skin of vertebrates. Note the arthropod characteristics, jointed appendages, segmented body, etc. This image is copyright Dennis Kunkel at www.