256 



BULLETIN 93, UNITED STATES NATIONAL MUSEUM. 



FIG. 81. TETRACLITA SQUAMOSA STALACTIFERA FORM CONFINIS. a, c, SCUTA AND ft, d, TERGA 



OF TWO INDIVIDUALS FROM ST. GEORGES ISLAND, GULF OF CALIFORNIA. 



TETRACLITA SQUAMOSA PANAMENSIS, new subspecies. 

 Plate GO, figs. 3-3&. 



1909. Tetradita porosa (Gmelin) PILSBRV, Proc. U. S. Nat. Mus., vol. 37, p. 

 64, pi. 16, fig. 2. 



Type.Cai. No. 58061, U.S.N.M., from Panama. 



Distribution. Panama to Peru. 



Form, thick wall, small orifice and fine pores as in T. s. milleporosa, 

 the external color gray or tea green with light purplish-gray stains, 

 the sheath slate-violet to dusky slate-violet. Diameter 30 to 40 mm. 



/ 



Scutum, very similar to that of T. s. stalactifera; often whitish in 

 the middle. Articular ridge and furrow narrow and small. Ad- 

 ductor ridge strongly developed, arcuate and long. 



Tergum decidedly narrower than in stalactifera or miNcporosa. 



I have seen a considerable number from Panama. While related to 

 T. s. milleporosa and T. s. stalactifera, it has a rather distinct aspect, 

 somewhat like typical T. squamosa. 



