. Bulletin of the British Museum (Natural History), Geology. 118 M. A. PARKES. arrickbyrne Hill Fig. 7 Locality map of the Carrigadaggan locality. Key as in Fig. 2. Preparation techniques Standard preparation methods were used. The measurements of all material (in millimetres) were made using vernier scale calipers or a micrometric graduated microscope eyepiece, both accurate to OT mm. The combination of camera, lenses and extension rings (Table 5) gave a range of magnifications of up to X5. The specimens were whitened with ammonium chloride sublimate before being photographed. Taxonomy and st
. Bulletin of the British Museum (Natural History), Geology. 118 M. A. PARKES. arrickbyrne Hill Fig. 7 Locality map of the Carrigadaggan locality. Key as in Fig. 2. Preparation techniques Standard preparation methods were used. The measurements of all material (in millimetres) were made using vernier scale calipers or a micrometric graduated microscope eyepiece, both accurate to OT mm. The combination of camera, lenses and extension rings (Table 5) gave a range of magnifications of up to X5. The specimens were whitened with ammonium chloride sublimate before being photographed. Taxonomy and statistical analysis In this study both multivariate and bivariate analyses have been utilized where the measurement data were adequate. Table 5 Magnifications obtained by different lens and extension ring combinations. AF Micro-Nikkor 55 mm f/28 x 1 AF Micro-Nikkor 55 mm f/2-8, PK11A, PK12, PK13 x2 24 mm lens reversed + PK11A x3 24 mm lens reversed + PK13 x4 24 mm lens reversed + PK11A + PK12 + PK13 x5 NOTE: All other combinations produce non-integer magnifications. Magnification less than XI necessitated the use of the AF Micro Nikkor 55 mm, but not fully extended. The magnification was calculated by comparison of the negative with the measured specimen size. For detailed discussion of statistical methodology in brachio- pod systematic work, reference can be made to Williams (1962), Harper (1984) and Temple (1987). In many older palaeontological references the use of statistics to define species is minimal or non-existent. For example, the funda- mental work of M'Coy (1846) quotes the length of most species described as a single value (in inches and lines, where a line = l/12th of an inch). No indication is given as to whether this is the length of a figured specimen or a subjec- tive assessment of the mean length of a sample. Here a pragmatic approach was taken, and measurements were made on any specimens worth measuring. Some measure- ments taken on slightly deformed material
Size: 1773px × 1409px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorbritishmuseumnaturalhistory, bookcentury1900, bookcoll
