Aasta | 1949 |
---|---|
Köide | 21 |
Number | 1 |
Leheküljed | 45-56 |
Tüüp | artikkel ajakirjas |
Keel | inglise |
Id | 50928 |
Abstrakt
Ordovician trilobites referable to Scutel- lum in a wide sense (Bronteus, Goldius auct.) have been reported from a number of localities in America, but the usual fragmentary nature of the specimens and the meager information available about the first described, Bronteus lunatus Billings, has discouraged their study. Most references in the literature are unsupported by figures, or have only a copy of Billings' original woodcut. The present paper summarizes the described species, and adds others which the writer has encountered. There has been no systematic attempt to bring together all the American material, although it is obvious from the lists in the literature that there are other undescribed forms. I am indebted to Dr. W. A. Bell, Geological Survey of Canada, Dr. Madeleine A. Fritz, Royal Ontario Museum of Palaeontology and Dr. J. Marvin Weller and M. S. Chappars of Walker Museum for permission to study specimens in their care. With two exceptions the photographs were made by Charles Corke of London, Ontario, under my direction.