. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. CONTRIBUTIONS TO THE KNOWLEDGE OF MARINE MOLLUSGA 491 merits: largest 'low-beaked' lower valve length 40, alt. 45 mm.; 'high-beaked' lower valves 45 X 55 and 30 X 60 mm.; the apertures measure respectively 38 x 38, 40 x 40 and 28 X 42 mm. The largest upper valve is 42 X 42 mm. The umbonal spiral is clock-wise in the lower, counter clock-wise in the upper valve. Lower valves with concentric ridges, more or less lamellose, sometimes strongly so, but irregular; lamellae undulate but not forming sep
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. CONTRIBUTIONS TO THE KNOWLEDGE OF MARINE MOLLUSGA 491 merits: largest 'low-beaked' lower valve length 40, alt. 45 mm.; 'high-beaked' lower valves 45 X 55 and 30 X 60 mm.; the apertures measure respectively 38 x 38, 40 x 40 and 28 X 42 mm. The largest upper valve is 42 X 42 mm. The umbonal spiral is clock-wise in the lower, counter clock-wise in the upper valve. Lower valves with concentric ridges, more or less lamellose, sometimes strongly so, but irregular; lamellae undulate but not forming separate squamae. In some specimens fine radial striae can be traced on some parts. Upper valve with concentric, more or less lamellose ridges, sometimes near the margin closely imbricate and markedly crinkly. Margin internally in both valves crenulate, but most of the specimens are worn. One upper valve is dull Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original South African Museum. Cape Town : The Museum
Size: 970px × 2576px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectnaturalhistory, booky
