EUCALODIUM. 19 



Most slender one (8 whorls) 251/2 mm. long., diam. 7; aper- 

 ture 6 long, 6 broad. 



Angangueo, State of Michoacan, Mexico, under leaves of 

 Agave americana (Hegewisch) ; Omiltepec, State of Guererro 

 (H. II . Smith). 



Bidimus truncatus PFR., Symb. Hist. Helic. i, p. 43 (1841) ; 

 Philippi's Abbild. neuer Conch, i, p. 55, pi. 1, f. 8; Monogr. 

 Helic. Vivent. ii, p. 154, and viii, p. 131 ; Malak. Blatt. xxii, 

 p. 37 (1872). REEVE, Conch. Icon, v, Bulimus, pi. 70, fig. 1 

 (not pi. 69, fig. 498) (young specimen). Cylindrella trim- 

 cat a (Pfr.), v. MART. Malak. Blatt. xii, p. 13 (1865). Euca- 

 lodium truncatum FISCH. & CROSSE, Miss. Scient. Mex., 

 Mollusca, i, p. 392. v. MART., Biologia, Moll., p. 264, pi. 16, 

 f . 3-9. Eucalodium martensii STREBEL, Beitr. Mex. Land- und 

 Siissw.-Conch. iv, p. 73, pi. 13, fig. 13, pi. 11, fig. 8(radula) 

 and 14 (jaw), pi. 12, fig. 3 (genitalia). ? Cylindrella trans- 

 aperta SOWB., Conch. Icon, xx, pi. 9, f. 77. 



Not Bidimus truncatus Brug., Encycl. Meth. i, p. 310, 

 Limn&a truncatida (Miill.). 



The figures and description are from von Martens' account 

 in the Biologia Centrali Americana, based upon numerous 

 specimens from Omiltepec, collected by Herbert H. Smith. 



A very peculiar, small species, long known by the young 

 shell only. The type of E. martensi Strebel is shown in 

 fig. 24. C. transaperta Sowb. (fig. 25) may possibly be re- 

 lated, but it differs in the form of the aperture and the wider 

 lip, and may belong to Urocoptis (q. v.). Its habitat is un- 

 known. 



(Group of E. speciosum. Sect. Rcsupinata v. Mart.). 



Resupinata v. MART., Biologia Centrali Americana, Mol- 

 lusca, p. 255 (Nov. 1897), for E. speciosum, edwardsianum, 

 de shay esiai turn. 



" Shell somewhat fusiform, narrowed below, last whorl 

 descending considerably beyond the suture, and the plane of 

 the aperture thus very oblique; color yellowish or brown." 

 Internal pillar very slender and straight. Type E. speciosum. 



This group differs from typical Oligostylus in the thin shell 



