ORTMANN : TERTIARY INVERTEBRATES. 
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82. Panopea subsymmetrica (Ortmann). 
PI. XXIX, Fig. 6. 
1899 Glycimeris subs. Ortmann, in: Amer. Journ. Sci., v. 8, p. 429. 
Very near the preceding species ( P. ibari ), but more swollen, not so 
much elongated, and posterior end not narrowed. 
Length, 69 mm; height, 45 mm; diameter, 18 mm. Apex at 28 from 
anterior end. Rel. H. : L. = 1 : 1.6. 
Remarks: Differs from the following species (P. regularis ) in the posi- 
tion of the apex (nearer to the middle), and the stronger convexity, 
especially of the posterior part of the shell. 
Record of specimens : Punta Arenas, horizon III (upper Magellanian), 
1 right valve. 
83. Panopea regularis (Ortmann). 
PI. XXX, Fig. i“’ 6 . 
1900 Glycimeris reg. Ortmann, in: Amer. Journ. Sci., v. 10, p. 371. 
Shell elongate, convex, with concentric lines of growth and undulations. 
Apex at one-third of the length, incurved. Anterior end rounded, pos- 
terior sub truncate, not narrower than the anterior. Ventral margin 
straight in the middle. 
Length, 101 mm (incomplete); height, 61 mm; diameter, ca. 30 mm; 
apex at 40 mm (Santa Cruz). 
Length, 78 mm; height, 45 mm; apex at 25 mm (San Julian). 
Length, 105 mm (incomplete); height, 75 mm; apex at 31 mm (Lake 
Pueyrredon). 
Remarks: This species differs from P. ibari: (1) in the anterior and 
posterior ends of the shell being equally high ; (2) in the straight lower 
margin ; (3) in the situation of the apex. It differs from P. subsymmetrica : 
in the more anterior apex and less convex shell ; from P. quemadensis 
in the more anterior apex and higher posterior end. P. nucleus v. Ih. 
(1899, p. 23, pi. 1, f. 7), from Santa Cruz, agrees in the position of the 
apex, but it is considerably narrower posteriorly, and I do not see 
any traces of the grooves or depressions described by v. Ihering as run- 
ning down from the apex (these grooves are not visible in v. Ihering’ s 
figure). 
