The American horseshoe crab ( Limulus polyphemus ) is one of four extant species in the Order Xiphosura, subphylum Chelicerata, and are evolutionarily more closely related to scorpions and spiders, than crabs. The basic structure, function, and physiology of these invertebrates and their internal organs are not well documented in the literature. In this study, the gastrointestinal system, with a focus on the stomach, of adult L. polyphemus were assessed by gross and histologic methods to further characterize the pyloric valve, the lining of the ventricular lumen, and the muscular tunics of the stomach. Determination of normal anatomical structure of this organ system, along with characterization of the esophagus and intestinal tract, will set a standard against which tissue abnormalities, such as those seen with disease or pathology were to arise, would allow for better interpretation.

中文翻译：

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成年鲎（Limulus polyphemus）胃肠道的组织学特征，特别是胃

美国鲎 (Limulus polyphemus) 是鲎目 Chelicerata 亚门的四种现存物种之一，在进化上与蝎子和蜘蛛的关系比螃蟹更密切。这些无脊椎动物及其内部器官的基本结构、功能和生理学在文献中没有很好的记录。在这项研究中，通过大体和组织学方法评估了成年 L. polyphemus 的胃肠系统，重点是胃，以进一步表征幽门瓣、心室腔的衬里和胃的肌肉外衣。确定该器官系统的正常解剖结构，以及食道和肠道的特征，将设定一个标准，针对该标准，组织异常，例如那些出现疾病或病理学的异常，