. Bulletins of American paleontology. < Q. en < Z ZOUSFANA TAOUERTA IGLI HARREZ BOULMANE AKACHA MAZZER ' ^ ' '"7^ â <- -J . L - 1 J3 r ^^ J. i_i_t^ 111^. T-rr 3 I and abundant pluiicolumnals in the collections might provide additional support for minor distances of transport or sorting with transport unless their absence reflects collection bias, which is a real possibility for columnals which are often considered to have little paleontological utility. The extent of collection bias is uncertain. It is con- sidered a strong factor concerning the lack of colum- nals, however, beca
. Bulletins of American paleontology. < Q. en < Z ZOUSFANA TAOUERTA IGLI HARREZ BOULMANE AKACHA MAZZER ' ^ ' '"7^ â <- -J . L - 1 J3 r ^^ J. i_i_t^ 111^. T-rr 3 I and abundant pluiicolumnals in the collections might provide additional support for minor distances of transport or sorting with transport unless their absence reflects collection bias, which is a real possibility for columnals which are often considered to have little paleontological utility. The extent of collection bias is uncertain. It is con- sidered a strong factor concerning the lack of colum- nals, however, because it is uncommon to find cups and thecae without associated columnals or pluricol- umnals. Until the Algerian area is more accessible for recollection and study, questions concerning collection bias with sedimentary and environmental relationships remain unanswered. Each of the 18 faunas listed (See Appendix, p. 70) is followed by comments on the diversity, dominance, and comparisons to equivalent faunas. It should be noted that none of these faunas compares with the large diversity of some time-equivalent faunas from Scotland (Wright. 1950-1960) and the United States (Bassler and Moodey, 1943). Stratigraphic information is insufficient to determine the exact horizon from which a few of the specimens were collected. These specimens are indicated by an asterisk (*) and are in- cluded in all of the faunas in which they might have been found. Columnal taxa are preceded by the symbol 0. Numbers in brackets following each taxon are the number of specimens. The faunas are discussed in or- der of oldest to youngest (Text-fig. 2). Akacha Formation (Visean) Koiyschisma sahanie (Breimer and Macurda. l'-)72) [I] Eclocriniis roiichi (Delpey, 1941) n. comb. [111 Barycrinidae? indeterminate [5] Balearocriniis pareyni n. sp. [1] Cromyocrinid? indeterminate | I ] Cladid indeterminate 3 111 Sagenocrinid indeterminate 2 111 The fauna of the Akacha Formation is moderately diverse for its small
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