Stages in spermatogenesis of two species of caecilians, Ichthyophis tricolor and Uraeotyphlus cf. narayani (Amphibia: Gymnophiona): Light and electron microscopic study.

abstract：:The vomeronasal system consists of a peripheral organ and the connected central neuronal networks. The central connections are sexually dimorphic in rodents, and in some species, parameters of the vomeronasal organ (VNO) vary with sex, hormonal exposure, body size and seasonality. The VNO of the dasyurid marsupial mou...

journal_title：Journal of morphology

authors： Aland RC,Gosden E,Bradley AJ

更新日期：2016-11-01 00:00:00

abstract：:The tubular accessory gland consists of a simple secretory epithelium surrounded by a muscular coat. Over the pupal instar, the gland increases ten-fold in volume and 15-fold in length. Pupal development is divisible into a phase of mitosis and one of cell growth. During the mitotic phase, cytoplasmic membranes are sp...

journal_title：Journal of morphology

authors： Happ GM,Happ CM

更新日期：1982-04-01 00:00:00

abstract：:Ultrastructural observations and glyoxilic acid-induced fluorescence of catecholamines indicate that tracts of axons lie at the base of the ciliary bands and run throughout their length in bipinnaria and brachiolaria larvae of Pisaster ochraceus. Two types of nerve cells occur at regular intervals within the ciliary b...

journal_title：Journal of morphology

authors： Burke RD

更新日期：1983-10-01 00:00:00

abstract：:Vibrissae or follicle-sinus complexes (F-SCs) are highly developed mammalian sensory structures. These blood-filled sinuses are richly innervated and possess novel mechanoreceptors. Although much is known regarding the function of F-SCs in terrestrial mammals, much less is known regarding marine carnivores such as pin...

journal_title：Journal of morphology

authors： Sprowls CD,Marshall CD

更新日期：2019-11-01 00:00:00

abstract：:Whole body studies of Plotosus tandanus revealed that ampullary pores occur over the entire body of the fish, but are in higher concentrations in the head region. These pores give rise to a short canal (50-60 microm) produced by columnar epithelial cells bound together by tight junctions and desmosomes. At the junctio...

journal_title：Journal of morphology

authors： Whitehead DL,Tibbetts IR,Daddow LY

更新日期：2003-02-01 00:00:00

abstract：:Hind foot drumming is a form of seismic signaling that plays a vital role in the communication of several Bathyergidae species. Hind foot drumming is initiated by the rapid movement of the whole hind limb by flexion and extension of the hip and knee. This study aimed to determine if morphological adaptations of the hi...

journal_title：Journal of morphology

authors： Sahd L,Bennett NC,Kotzé SH

更新日期：2020-04-01 00:00:00

abstract：:Cyprinids constitute the largest fish family and are characterized by their pharyngeal teeth. The masticatory mechanism is still poorly understood. The complex of structures that determine the movements of pharyngeal teeth and chewing pad in the carp (Cyprinus carpio L.) is analyzed. Activities in 16 head muscles of a...

journal_title：Journal of morphology

authors： Sibbing FA

更新日期：1982-05-01 00:00:00

abstract：:Regional variation in the vertebral column of several species of salamanders (families Ambystomatidae, Salamandridae and Plethodontidae) is analyzed. Measurements of three dimensions, centrum length, prezygapophyseal width, and transverse process length, provide the data. Ontogenetic, interspecific, intergeneric and i...

journal_title：Journal of morphology

authors： Worthington RD,Wake DB

更新日期：1972-07-01 00:00:00

abstract：:Detailed descriptions of mammalian sperm morphology across a range of closely related taxa are rare. Most contributions have been generalized descriptions of a few distantly related mammalian species. These studies have emphasized a generalized ungulate sperm morphology, but have not underscored several important morp...

journal_title：Journal of morphology

authors： Downing Meisner A,Klaus AV,O'Leary MA

更新日期：2005-02-01 00:00:00

abstract：:Four species of Phocidae, or true seals, inhabit the waters surrounding the Antarctic continent. These animals are thought to have different diving capabilities. The Weddell seal, Leptonychotes weddelli, is known to be capable of attaining depths up to 600 meters. The respiratiory system of the Weddell seal shows the ...

journal_title：Journal of morphology

authors： Boyd RB

更新日期：1975-11-01 00:00:00

abstract：:Electron microscopy of spermatogenesis in the Hawaiian red lobster, Enoplometopus occidentalis (Randall), has revealed unusual activity within membranous organelles. Mitochondria-like bodies (MLB-1) seen first in spermatogonia appear in primary spermatocytes to swell and fuse as the cytoplasm develops annulate lamella...

journal_title：Journal of morphology

authors： Haley SR

更新日期：1986-10-01 00:00:00

abstract：:Scanning electron and light microscopic studies reveal significant changes in the endometrial histophysiology of the soft-shelled turtle Lissemys punctata punctata during its seasonal reproductive cycle. Scanning electron microscopy shows the entire oviductal mucosa to be only slightly folded throughout the non-breedi...

journal_title：Journal of morphology

authors： Sarkar S,Sarkar NK,Maiti BR

更新日期：1995-04-01 00:00:00

abstract：:The forelimbs, along with the crania, are an essential part of the prey-killing apparatus in cats. Linear morphometrics of the forelimbs were used to determine the morphological differences between felids that specialize on large prey, small prey, or mixed prey. We also compared the scaling of felid forelimbs to those...

journal_title：Journal of morphology

authors： Meachen-Samuels J,Van Valkenburgh B

更新日期：2009-06-01 00:00:00

abstract：:The phylogenetic position of bryozoans has been disputed for decades, and molecular phylogenetic analyzes have not unequivocally clarified their position within the Bilateria. As probably the most basal bryozoans, Phylactolaemata is the most promising taxon for large-scale phylogenetic comparisons. These comparisons r...

journal_title：Journal of morphology

authors： Schwaha T,Handschuh S,Redl E,Walzl MG

更新日期：2011-03-01 00:00:00

abstract：:In viviparous, teleost fish, with postfertilization maternal nutrient provisioning, embryonic structures that facilitate maternal-fetal nutrient transfer are predicted to be present. For the family Poeciliidae, only a handful of morphological studies have explored these embryonic specializations. Here, we present a co...

journal_title：Journal of morphology

authors： Panhuis TM,Fris M,Tuhela L,Kwan L

更新日期：2017-12-01 00:00:00

abstract：:South American Pipidae show a unique reproductive mode, in which the fertilized eggs develop in temporarily formed brood chambers of the dorsal skin after eggs have been deposited on the back of the female. We studied the skin incubation of Pipa carvalhoi using light microscopy and scanning electron microscopy. The sk...

journal_title：Journal of morphology

authors： Greven H,Richter S

更新日期：2009-11-01 00:00:00

abstract：:The olfactory epithelium and the vomeronasal organ of the Japanese striped snake were examined by lectin histochemistry. Of the 21 lectins used in the study, all lectins except succinylated-wheat germ agglutinin (s-WGA) showed similar binding patterns in the vomeronasal receptor cells and the olfactory receptor cells ...

journal_title：Journal of morphology

authors： Kondoh D,Yamamoto Y,Nakamuta N,Taniguchi K,Taniguchi K

更新日期：2010-10-01 00:00:00

abstract：:During ontogeny, the apical and basal components of dicamptodontid teeth exhibit three major developmental stages: nonpedicellate, subpedicellate, and pedicellate. Premetamorphic larvae tend to have nonpedicellate teeth, incompletely or recently metamorphosed individuals tend to have subpedicellate teeth, and fully tr...

journal_title：Journal of morphology

authors： Beneski JT Jr,Larsen JH Jr

更新日期：1989-02-01 00:00:00

abstract：:The structure of contact chemoreceptors in the cibariopharyngeal pump of the moth Trichoplusia ni (Lepidoptera: Noctuidae) is described. Two types of receptors designated A and B are located on the floor of the pump. Two groups of 9-12 A receptors are located in the anterior part of the pump, and two groups of two B r...

journal_title：Journal of morphology

authors： Eaton JL

更新日期：1979-04-01 00:00:00

abstract：:Swimming crabs of the taxon Portunoidea show specialized, paddle-shaped fifth pereiopods (P5), which play a role in these crabs' ability to swim. In this study, the morphology of the fifth pereiopod in swimming and non-swimming crabs was studied in detail and the mobility in the articulations between podomeres was cal...

journal_title：Journal of morphology

authors： Schmidt M,Hazerli D,Richter S

更新日期：2020-12-01 00:00:00

abstract：:The larval development of "conchostracans" has received only scattered attention. Here I present the results of a study on the larval (naupliar) development and the metamorphosis of Lynceus brachyurus, a member of the bivalved branchiopod order the Laevicaudata. Lynceus brachyurus is the only species of the "Conchostr...

journal_title：Journal of morphology

authors： Olesen J

更新日期：2005-05-01 00:00:00

abstract：:The feeding mechanisms of two labrid fishes (Cheilinus chlorurus and C. diagrammus: Labridae: Perciformes) are modeled using four-bar linkage theory from mechanical engineering. The actions of the feeding mechanisms are simulated by a computer program that uses morphometric data to calculate the geometry of mechanism ...

journal_title：Journal of morphology

authors： Westneat MW

更新日期：1990-09-01 00:00:00

abstract：:Bone is a dynamic tissue adapting to loading according to "Wolff's law of bone adaptation." During very early life, however, such a mechanism may not be adequate enough to adapt to the dramatic change in environmental challenges in precocial species. Their neonates are required to stand and walk within hours after bir...

journal_title：Journal of morphology

authors： Gorissen BM,Wolschrijn CF,van Vilsteren AA,van Rietbergen B,van Weeren PR

更新日期：2016-07-01 00:00:00

abstract：:We described the topography and morphometry of the testicular artery, pampiniform plexus veins, and indirect connections between them in the spermatic cord of the bull. Sixty microcorrosive casts of bovine spermatic cords were analyzed macroscopically, by stereomicroscopy, and by scanning electron microscopy. The aver...

journal_title：Journal of morphology

authors： Polguj M,Jȩdrzejewski KS,Topol M

更新日期：2011-04-01 00:00:00

abstract：:Clasper gland morphology and development in Potamotrygon magdalenae and its relation with the acquisition of reproductive maturity is described in males of different developmental stages (embryos, neonates, juveniles, and reproductively active and resting adults). The glands are subcutaneous masses in the proximal bas...

journal_title：Journal of morphology

authors： Anaya-López P,Ramírez-Pinilla MP

更新日期：2017-03-01 00:00:00

abstract：:The usual pigmentation pattern in mammalian skin consists of fixed melanocytes in the basal layer of the epidermis, supplying keratinocytes with melanosomes. We observed that the glabrous skin (rhinaria and footpads) of dogs deviates from this pattern. In dogs, melanocytes are found in both the dermis and epidermis. T...

journal_title：Journal of morphology

authors： Elofsson R,Kröger RHH

更新日期：2018-08-01 00:00:00

abstract：:We studied early neurulation events in vitro by transplanting quail Hensen's node, central prenodal regions (before the nodus as such develops), or upper layer parts of it on the not yet definitively committed upper layer of chicken anti-sickle regions (of unincubated blastoderms), eventually associated with central b...

journal_title：Journal of morphology

authors： Callebaut M,Van Nueten E,Van Passel H,Harrisson F,Bortier H

更新日期：2006-07-01 00:00:00

abstract：:The red pulp of the spleens of the short-finned pilot whale (Globicephala macrorhynchus) and the Pacific bottle-nosed dolphin (Tursiops truncatus gilli) (Odontoceti) were examined by light and electron microscopy and found to comprise two venous layers, an inner and an outer. The inner layer is homologous to the inter...

journal_title：Journal of morphology

authors： Tanaka Y

更新日期：1994-08-01 00:00:00

abstract：:A morphological comparison of the spermatozoa of the octopods Bathypolypus bairdii and B. sponsalis has been carried out by electron microscopy. Although the mature spermatozoon of B. bairdii is longer and thinner than that of B. sponsalis, its general ultrastructure is similar except for some minor differences. Their...

journal_title：Journal of morphology

authors： Roura A,Guerra A,González AF,Pascual S

更新日期：2010-02-01 00:00:00

abstract：:The colugos, or flying lemurs (Dermoptera), are arboreal gliding mammals that are commonly grouped with tree-shrews (Scandentia) and Primates in the superorder Euarchonta. However, little is known about the head and neck muscles of these gliding mammals. This raises difficulties for the discussion of not only the func...

journal_title：Journal of morphology

authors： Diogo R

更新日期：2009-01-01 00:00:00