Maximum length 7 cm. A plumpish shell which may be as wide as it is long. The colour is dirty white or brown, the periostracum chestnut-brown. The drawing, which is from the old-fashioned but ever-useful manual of Joubin and Le Danois, shows the ‘praire vivante’ and also brings out clearly the sculpture of concentric ridges on the shell, which develop into wart-like spines on the margins and account for the weird name warty venus.
