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SMITHSONIAN MISCELLANEOUS COLLECTIONS
VOL. 57
| DESCRIPTION OF PLATE 24 | ||||
| PAGE | ||||
| Neolenus serratus (Rominger) | 190 | |||
| Fig. | 1. | (Natural size.) A partly exfoliated specimen, showing (a') an antenna, numerous thoracic legs (thl), and jointed caudal rami (cr). The caudal rami have been dragged backward, pulling with them a portion of the under edge of the ventral lining of the body cavity. U. S. National Museum, Catalogue No. 57656. | ||
| 1a. | (Natural size.) Pygidium with the caudal rami extending out from beneath it in their probable natural position. U. S. National Museum, Catalogue No. 57657. | |||
| Ptychoparia cordilleræ (Rominger) | 190 | |||
| Fig. | 2. | (✕6.) Dorsal view of a specimen from which the dorsal shield has been removed, leaving the branchiæ (br) exposed; also a few of the thoracic legs (thl). U. S. National Museum, Catalogue No. 57658. | ||
| Mollisonia symmetrica Walcott | 196 | |||
| Fig. | 3. | (Natural size.) Dorsal view of the type specimen found in the Stephen formation on Mount Stephen above Field, locality (14s). U. S. National Museum, Catalogue No. 57659. | ||
| Tontoia kwaguntensis Walcott | 199 | |||
| Fig. | 4. | (✕2.) Dorsal view of a cast made in the natural mold, which is the type specimen. From the Tonto sandstone, Kwagunt Valley, Grand Canyon, Arizona, locality (73). U. S. National Museum, Catalogue No. 57660. | ||
| Mollisonia gracilis Walcott | 197 | |||
| Fig. | 5. | (✕2.5.) Dorsal view of the type specimen of the species and genus. The specimen is laterally compressed. U. S. National Museum, Catalogue No. 57661. | ||
| Mollisonia ? rara Walcott | 198 | |||
| Fig. | 6. | (Natural size.) A fragment of this species, showing the form of the ends of the thoracic segments. U. S. National Museum, Catalogue No. 57662. | ||
| 7. | (✕2.) A small crushed specimen, showing a portion of the cephalic shield, thoracic segments, and pygidium. U. S. National Museum, Catalogue No. 57663. | |||
The specimens represented by figures 1, 1a, 2, 5, 6, and 7 are from locality (35k) Middle Cambrian: Burgess shale member 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.
