258 BULLETIN 181, UNITED STATES NATIONAiL MUSEUM 



APEROSTOMA (APEROSTOMA) CAUCAENSE (Da Costa) 

 Plate 37, Figubes 10, 11 



1801. Neocyclotus caucaensn Da Costa, Proc. Malac. Soc. London, vol. 4, p. 240, 



pi. 24, fig. 9. 

 1923. Poteria (Neocyclotus) caucacnsis H. B. Bakeb, Occ. Pap. Mus. Zool. Univ. 



Michigan, No. 137, p. 41. 



We have not seen specimens of this species and so give a trans- 

 lation of Da Costa's description and copy his figure : 



Shell moderately profoundly umbilicated, subdiscoid, vivid oliva- 

 ceous green with the interior of the aperture white and narrowly 

 banded at and below the periphery. Whorls 4, impressed at the 

 suture; the last canaliculate below. Aperture circular; peristome 

 thin, with a cut in the basal lip. Greater diameter, 30 mm.; lesser, 

 23.5 mm. 



Habitat: Province of Cauca, Colombia. 



Da Costa then adds : "Of the two specimens received of this singu- 

 lar shell one was returned by the writer in hopes that others might 

 be discovered, but without result. In both of the shells sent the 

 fissure on the lip occurs in precisely the same place, just below the 

 shallow canal that surrounds the base; a similar fissure is found 

 in N. giganteus, var. Fischsrianus, Hid., from Ecuador, but that 

 form has no canal on the base." 



This species looks to us as if its peculiarities were due to an in- 

 jury; however, not having seen it or anything like it, we merely 

 cite it as described and figured. 



APEROSTOMA (APEROSTOMA) COLOMBIENSE (Da Costa) 



Plate 38, Figubes 22-24 



1901. Neocyclotus colomUensis Da Costa, Proc. Mai. Soc. London, vol. 4, p. 240, 

 pi. 24, fig. 7 (not Cyclostoma colambiensis Ferussac MS., Orbigny, 1835). 



1923. Poteria (Neocyclotus) colombicnsis H. B. Bakek, Occ. Pap. Mus. Zool. 

 Univ. Michigan, No. 137, p. 43. 



Shell helicoid, the upper portion brownish olivaceous. There is 

 a narrow light band immediately above the periphery and a narrow 

 dark chestnut-colored band immediately below the periphery. There 

 is a second dark chestnut-colored band of the same intensity and 

 width on the middle of the base. Between these two there are 

 numerous slender, spiral hairlines of dark brown. The rest of the 

 base is olivaceous horn colored; interior of aperture bluish white. 

 The nucleus consists of 2 rather large, well-rounded, small turns. 

 The postnuclear whorls are strongly rounded; the last one drops 

 considerably below the periphery of the preceding turn and bears 

 a conspicuous rounded cord at the appressed summit. Below this 

 cord is an impressed groove. The postnuclear whorls are marked by 



