 In his 1935 work Handbuch der systematischen Weichtierkunde ( Handbook of Systematic Malacology ) , Johannes Thiele introduced a mollusc taxonomy based upon the 1909 work by Cossmann and Peyrot . Thiele 's system divided the bivalves into three orders . Taxodonta consisted of forms that had taxodont dentition , with a series of small parallel teeth perpendicular to the hinge line . Anisomyaria consisted of forms that had either a single adductor muscle or one adductor muscle much smaller than the other . Eulamellibranchiata consisted of forms with ctenidial gills . The Eulamellibranchiata was further divided into four suborders : Schizodonta , Heterodonta , Adapedonta and Anomalodesmata . 
