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SMITHSONIAN MISCELLANEOUS COLLECTIONS
VOL. 57
DESCRIPTION OF PLATE 25
| Legend: | |
| c = carapace. | m=third appendage=mandible. |
| x=posterior spines or lobes of carapace. | m'=fourth appendage=maxillula. |
| e=eye. | m"=fifth appendage=maxilla. |
| lb=labrum. | i=intestine or alimentary canal. |
| th=thorax. | thi=thoracic legs [endopodites]. |
| ab=abdomen. | l=setiferous jointed exopodite. |
| a' = antennule ?. | br=branchial lobes or gills [epipodites]. |
| a"=antennæ. |
| PAGE | ||||
| Marrella splendens Walcott (see pl. 26) | 193 | |||
| Fig. | 1. | (✕4.) Dorsal view of a crushed specimen in which the juncture of the antennules ? (a') and the carapace is clearly shown. U. S. National Museum, Catalogue No. 57664. | ||
| 2. | (✕4.) Dorsal view illustrating the segments of the body, carapace and its great posterior spines. U. S. National Museum, Catalogue No. 57665. | |||
| 3. | (✕4.) Dorsal view of a partly exfoliated specimen showing the antennæ (a"), a feather-like maxillula, and one of the remarkable setiferous exopodites. U. S. National Museum, Catalogue No. 57666. | |||
| 4. | (✕3.) A specimen crushed sideways so as to force the eye (e) out prominently on the left side. U. S. National Museum, Catalogue No. 57667. | |||
| 5. | (✕3.) A sliglitly distorted specimen illustrated to show the eyes (e). U. S. National Museum, Catalogue No. 57668. | |||
| 6. | (✕4.) Dorsal view of a specimen showing the setiferous exopodites as they lie one on the other with the setæ pointing forward and outward. U. S. National Museum, Catalogue No. 57669. | |||
All of the specimens illustrated on Plate 25 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.
