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SMITHSONIAN MISCELLANEOUS COLLECTIONS
VOL. 57
| DESCRIPTION OF PLATE 8 | ||||
| cr. Central ring. p. Digitate tentacle. rc. Radial canals. s. Stomach. | ||||
| PAGE | ||||
| Peytoia nathorsti Walcott | 56 | |||
| Fig. | 1. | Subumbrella view of the type specimen of the genus and species. Natural size. The four large lobes are marked ✕. U. S. National Museum, Catalogue No. 57538.
A portion of an annelid, Ottoia prolifica, n. g. and n. sp., is shown above the medusa. | ||
| 2. | Subumbrella view of a second specimen that differs in detail from the specimen represented by figure 1. It also shows the short spines about the oral aperture more clearly. Natural size. U. S. National Museum, Catalogue No. 57539. | |||
| Both specimens illustrated are compressed in the shale and show no traces of canals or other portions of the medusa within the subquadrate central area. | ||||
| Eldonia ludwigi Walcott (see also text fig. 5 and pls. 9-12) | 46 | |||
| Fig. | 3. | An individual preserved as a thin film in the shale. Natural size. U. S. National Museum, Catalogue No. 57540. | ||
| This shows a digitate tentacle (p) and radial canals (rc) extending to and beyond the central stomach (s). The peripheral margin of the umbrella is not definitely outlined. Traces of the radial canals are seen crossing the stomach on the left side.
A small individual compressed so as to give a partial side view, is shown on the left. This preserves traces of radial canals and stomach. | ||||
All of the specimens illustrated on this plate are from locality (35k) Middle Cambrian; dark siliceous shales in the Burgess shale of the Stephen formation on the west slope of the ridge between Mount Field and Wapta Peak, one mile (1.6 km.) northeast of Burgess Pass, above Field, British Columbia.
