20 EUC ALODIUM. 



and greater free deviation and descent of the last whorl ; but 

 it is somewhat difficult to assort the species into the two groups. 

 Several of them need re-examination to determine the char- 

 acter of the axis. 



E. densecostatum, speciosum and cereum are very densely 

 rib-striate ; the others have more spaced or weak stria?, and are 

 doubtfully referable to this group. 



E. DENSECOSTATUM Strebel. PI. 1, fig. 4. 



Shell thick, rather cylindric, with about 8 whorls remain- 

 ing; somewhat tapering above; suture somewhat margined. 

 Last whorl only shortly free, at first pretty sharply keeled be- 

 low, the keel then becoming a low cord. The aperture is pretty 

 round, somewhat angular above; peristome shortly and rather 

 strongly expanded and thickened. The internal pillar is 

 rather straight throughout, the columellar fold short, 

 deeply situated, and formed as in E. edwardsianum and 

 boucardi. The most peculiar feature of the species is the 

 sculpture, which consists of exceedingly closely placed but not 

 very fine, slightly curved riblets (about 170 on the last whorl, 

 which is 12 mm. wide). The intervals are so narrow that 

 no sculpture can be seen in them. 



Eastern Mexico: Orizaba (Botteri). 



E. densecostatum STREBEL, Beitr. iv, p. 71, pi. 6, f. 10(1880). 

 -v. MART., Biologia, Moll., p. 261. 



No other species has similar sculpture; E. boucardi has a 

 similar form, but coarser sculpture. E. speciosum Dkr. 

 (1 iifers in the shape of the shell, the whorls and the more spaced 

 riblets. Described from two dead discolored specimens. 



E. SPECIOSUM (Dunker) . PI. 2, figs. 1, 2, 3. 



Shell rimate, nearly cylindric, truncate, rather solid, sub- 

 diaphanous, whitish, silky, minutely costulate-striate, the stria? 

 lightly arcuate, more obsolete in the middle of the whorls, 

 whorls 91/0, a little convex, slightly increasing, the last free in 

 fronl, shortly descending, angular above. Columella with a 

 twist or fold. Aperture obliquely oboval, angular above; 

 prrisloine narrowly ivflrxed throughout. Length 21, diam. 

 lines [about 42, 11 mm.] (Dim AT/-). 



