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Crinoidea (Crinoids)

      Crinoids are marine animals that make up the class Crinoidea of the echinoderms (phylum Echinodermata). Crinoidea comes from the Greek word krinon, "a lily", and eidos, "form". They live both in shallow water and in depths as great as 6,000 meters. Sea lilies refer to the crinoids which, in their adult form, are attached to the sea bottom by a stalk. Feather stars or comatulids refer to the unstalked forms. Crinoids are characterized by a mouth on the top surface that is surrounded by feeding arms. They have a U-shaped gut, and their anus is located next to the mouth. Although the basic echinoderm pattern of fivefold symmetry can be recognized, most crinoids have many more than five arms. Crinoids usually have a stem used to attach themselves to a substrate, but many live attached only as juveniles and become free-swimming as adults. There are only a few hundred known modern forms, but crinoids were much more numerous both in species and numbers in the past. Some thick limestone beds dating to the mid- to late-Paleozoic are almost entirely made up of disarticulated crinoid fragments.

Source: http://en.wikipedia.org/wiki/Crinoidea
lilijice
Img. 81:
Acanthocrinus PP1247
Acanthocrinus PP1245
Acanthocrinus PP1246
AsperocrinusUreš et al. (1999), fig. 1A HL52
Beyrichocrinus humilis p1245
Bohemicrinus pulverens JH316
Bohemicrinus pulverens p5878
Calceocrinidae RP133
Calceocrinidae RP132
Calceocrinidae RP143
Calceocrinidae RP130
Calceocrinidae RP146
Calceocrinidae RP131
Caleidocrinus multiramus KP263
Caleidocrinus multiramus CW2031
Caleidocrinus multiramus BL83
Caleidocrinus multiramus KP946
Caleidocrinus multiramusfoto p4923
Caleidocrinus multiramus KP433
Caleidocrinus multiramus p4950

Virtual museum of the Czech Geological Survey, www.geology.cz, (C) Czech Geological Survey, 2011, v.0.99 [13.12.2011]