28 



MOLLUSCA IN THE MaYA LoWLANDS 



Chama echinata Broderip 



Illustration: Keen, 1958, fig. 239. 



Modern distribution: Pacific. 



Archaeological occurrence: 

 TIKAL: 28 unworked, not dated; 4 slighdy 

 altered, Early Classic (M— MS, "Pseudochama 

 echinata"). 



Chama florida Lamarck 



Illustration: Plate x-],d,dd. 



Modern distribution: East coast, from Turneffe 

 Islands to Isla Contoy, and the offshore atolls. Not 

 collected on north or west coasts. 



Archaeological occurrence: 



ISLA CANCUN MIDDEN: 8 unworked. For- 

 mative. 



Chama macerophylla Gmelin 



Illustration: Plate 'i-l,a,aa. 



Modern distribution: Common on all three coasts, 

 from Belize, B.H., to Isla Aguada, Camp. Also 

 on the offshore atolls. 



Archaeological occurrence: 



ISLA CANCUN MIDDEN: 13 unworked, For- 

 mative. 



SAN JOSE: i unworked, within cache, "probably 

 San Jose III" (T, p. 181; this shell illustrated in 

 Richards and Boekelman, 1937, pi. 6). 

 COROZAL: (Burial mound at "Rio Hok Skum" 

 excavated by Gann): i unworked, which may 

 have derived from a fossil deposit {ibid., p. 169, 

 pi. 6). 



Chama sarda Reeve 



Illustration: Plate il,c,cc. 



Modern distribution: Common on east coast, Tur- 

 neffe Islands, B.H., to Isla Mujeres, Q.R. Also 

 offshore atolls. Rare on north coast; collected at 

 Telchac Puerto and Chavihau. Not collected on 

 west coast. 



Archaeological occurrence: 

 ISLA CANCUN MIDDEN: 38 unworked, For- 

 mative. 



Chama sinuosa Broderip 



Illustration: Plate 17, £■,<?'. 



Modern distribution: East coast only, Turneffe 

 Islands, B.H., to Isla Contoy, Q.R. 



Archaeological occurrence: 



ISLA CANCUN MIDDEN: 50 unworked, For- 

 mative. 



Pseudochama radians (Lamarck) 



Illustration: Plate ijJJ'. 



Modern distribution: All three coasts from Turneffe 

 Islands to Isla Carmen, Camp., and the offshore 

 atolls. 



Archaeological occurrence: 



ISLA CANCUN MIDDEN: i unworked. For- 

 mative. 



Family: CARDIIDAE (cockleshells) 



Trachycardium egmontianum (Shuttleworth) 



This form has not been collected from the penin- 

 sula, where it almost certainly is replaced by the 

 closely related but distinct species T. isocardia. The 

 latter has been collected at 25 stations, from Isla 

 Cancun, Q.R., to Isla Carmen, Camp. 



Moholy-Nagy reports 31 unmodified T. egmonti- 

 anum from Tikal. These should be re-examined. It 

 is probable that they are actually T. isocardia. 



Trachycardium isocardia (Linne) 



Illustration: Plate 18, a, aa. 



Modern distribution: Common on all three coasts 

 from Isla Cancun, Q.R., to Isla Carmen, Camp. 



Archaeological occurrence: 

 DZIBILCHALTUN: 58 unworked, from all 

 periods (Table 2), fourteen of these among the 

 raw materials in one of the Late Early period 

 "jewelers' caches;" only two reasonably complete 

 valves appeared. 



MAYAPAN: Probably Decadent period, listed 

 in collection but not illustrated (P, p. 387). 

 TIKAL: See T. egmontianum above. 



Trachycardium magnum (Linne) 



Illustration: Plate 18, c,cc. 



Modern distribution: Rare. Collected only at Isla 

 Mujeres, Isla Cancun, and Alacran Reef. 



Archaeological occurrence: 



ISLA CANCUN MIDDEN: 2 unworked, For- 

 mative. 



UAXACTUN: Listed in RR (p. 199) and K 

 (p. 61) as "Cardium magnum." No illustration; 

 archaeological association not given. 



Trachycardium muricatum (Linne) 



Illustration: Plate i8,b,bb. 



Modern distribution: Common on all three coasts, 



from Belize, B.H., to Isla Aguada, Camp. Cayo 



Areas, 



