Crinoid (stem)

Object/Artifact

-

Crater Rock Museum

Name/Title

Crinoid (stem)

Entry/Object ID

2011.57.71 (a),(b)

Description

Description: Phylum: Echinodermata Class: Crinoidea Common Name: Crinoid Stems Age: Mississippian Location: Unknown Description: (2) crinoid stem specimens. One is columnarn with bands running the entire length. Somewhat segmented blocks. The second is columnar but flat. Colors are gray to light brown bands with some dull yellow. Physical Characteristics: 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".[1] They live both in shallow water and in depths as great as 6,000 meters.[citation needed] Sea lilies refer to the crinoids which, in their adult form, are attached to the sea bottom by a stalk.[2] Feather stars[3] or comatulids[4] 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. Kingdom: Animalia (Animals) Class: Crinoidea Phylum: Echinodermata

Collection

Museum Collection of Fossils

Acquisition

Accession

2011.57

Source or Donor

Museum Collection of Fossils

Acquisition Method

Long-term Loan

Dimensions

Dimension Notes

(a)- 2.250"x.750"x.500" (b)- ..750"x.675"x.675"

Location

Location

Container

Center

Drawer

2nd Shelf

Shelf

Right

Cabinet

Case # 51

Wall

North

Room

Delmar Smith Hall

Building

Crater Rock Museum

Category

Permanent