A varied collection of free-living polyclad flat worms taken in dredge hauls or removed from fouling communities. Collections may include Stylochus ellipticus, S. zebra, and Prostheceraeus floridanus. Some species swim like butterflies. Bdelloura candida, a commensal of the horseshoe crab is also included. Most likely available October through April. PL-310 HORSESHOE CRAB FLATWORM, Bdelloura candidaThese small white triclad flatworms occur on the legs of horseshoe crabs, adhering by glandular caudal adhesive disk. Scraped from the mouth and legs of kicking, scrambling crabs, Bdelloura is ready for a variety of studies. Since it lacks pigment, internal organs are clearly visible through body walls. To demonstrate their keen chemotactic response, the worms may be placed in a vial that opens into a Y-shaped tube with one terminal containing horseshoe crab juice and the other without juice. Invariably, the worms will crawl towards the host fluid. Size: 0.5-1 cm. PL-320 OYSTER FLATWORM, Stylochus ellipitcusThe grayish tan flatworm slithers down into the crannies of oysters and barnacles and remains hidden to even the trained eye. However, when the water in the holding trays or buckets begin to stagnate, out they come crawling up the sides and float on the surface. Size: 1/2-1 inch long. PL-330 ZEBRA FLATWORM, Stylochus zebra has a yellowish tan body and a vast network of zebra like stripes. Sporadically available in later summer and fall months, it dwells almost exclusively in the ascidian Ecteinascidia turbina.