. Bulletin. Natural history; Natuurlijke historie. Fig. 5. Morphotype-variability plots representing the shapes of eight groups that correspond to species described here. A, 6". kirschi; B, 5. olseni; C, S. inrginiae; D, 6'. thomsoni; E, 5. euthenius; F, 5'. convalis; G, 5'. redfieldii; H, S. schaefferi. The outline for each species is a tracing from an individual specimen (in most cases, the holotype). For each additional specimen considered, the overall shape (at a standard size) and fin positions were superimposed (see description in text) and morphological landmarks were plotted on th
. Bulletin. Natural history; Natuurlijke historie. Fig. 5. Morphotype-variability plots representing the shapes of eight groups that correspond to species described here. A, 6". kirschi; B, 5. olseni; C, S. inrginiae; D, 6'. thomsoni; E, 5. euthenius; F, 5'. convalis; G, 5'. redfieldii; H, S. schaefferi. The outline for each species is a tracing from an individual specimen (in most cases, the holotype). For each additional specimen considered, the overall shape (at a standard size) and fin positions were superimposed (see description in text) and morphological landmarks were plotted on the original tracing. Thus, B represents a single individual while H represents variation in shape and fin positions of seven individuals. Morphological landmarks recorded for each fish were anleriormost tip of snout; origin of dorsal fin; base of the axial lobe of the tail; origin of pelvic fin (left or right depending on the orientation of the fish); and origin of pectoral fin (left or right depending on the orientation of the fish). Drawings all standardized for standard length. GROUPING BY SHAPE The most useful tool for sorting these fishes by shape was a Goodkin viewer. A Goodkin viewer projects an enlarged or reduced image of an opaque object, such as a fossil, onto a drawing surface. With the aid of this viewer, tracings of individual fish were easily standardized for size and then grouped by shape. In doing so, my assumption was that shape changes little as a function of size over the relevant size range (7-12 cm). My procedure for grouping was to begin with the shape of one individual and test successive shapes against it as follows: I chose a well-preserved fish and using the Goodkin viewer traced its outline and marked the origins of its fins on tracing paper. I then put another fish under the viewer and compared it with the tracing. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration a
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Keywords: ., bookcentury1900, bookcollectionbiodiv, booksubjectnaturalhistory
