Product Details The dogfish shark, a member of the class Chondrichthyes, is a popular dissection specimen in general biology and anatomy courses. It is useful for learning about cartilaginous fish and for studying comparative and vertebrate anatomy. Pregnant specimens allow for a thorough investigation of advanced female reproductive structures and are ideal for students working in pairs or small groups. Pregnant dogfish sharks have many characteristics intriguing to students, including their: Ovaries Uteri containing embryos and attached yolk sac Cartilaginous skeleton Five pairs of gill slits Two-chambered heart Spiral intestine J-shaped stomach Lack of a swim bladder and operculum Product Features Double injected (red arteries and yellow hepatic system) for in-depth study of the arterial and hepatic portal systems Pregnant ideal for thorough investigation of female reproductive anatomy Soaked in Carosafe®, then individually packed and shipped in a vacuum-sealed bag for easy distribution Price listed is for 1 specimen Carosafe® Carosafe® preservative and holding solution for biological specimens contains no formaldehyde and is not a tissue fixative. Most Carosafe® specimens were first preserved with a formalin solution and then washed before placement in Carosafe®. Specimens are held in Carosafe® prior to shipment, producing formalin-preserved specimens that, when dissected, minimize formaldehyde exposure. Learn More. NOTE: Based on seasonal availability, substitution of shark genus and species may occur. Possible substitutes include the brown smooth-hound shark ( Mustelus henlei ) and the Atlantic blacktip shark ( Carcharhinus limbatus ). Dissection protocols and internal anatomy are the same as the traditional dogfish shark.