HOLOSPIRA. 103 



Cylmdrella microstoma PFR., P. Z. S., 1861, p. 27; Malak. 

 Blatter viii, 1861, p. 81 ; Monogr., vi, p. 390. Holospira 

 microstoma Pfr., FISCH. & CROSSE, Miss. Sclent. Mex., Moll., 

 i, p. 337, pi. 17, f. 9. v. MART., Biologia, p. 278. 



The interior is unknown, but it probably belongs to Ccelo- 

 stemma, differing from H. elizabethce and strebeliana in the 

 angular base, and from the latter in color and the longer ter- 

 minal cone. The figures are from Fischer & Crosse. 



56. H. IMBRICATA (v. Martens). PI. 15, figs. 1, 2. 



Shell imperforate, obovate, swollen above, then passing into 



short cone, rather solid, ribbed, gray- whitish ; the apex en- 

 ire, projecting. Whorls 16, flat, the first 2 smooth, following 



rather rapidly increasing, sculptured with strong oblique 

 ibs, the succeeding 4 whorls more slowly decreasing in cali- 

 >re, some being over-lapped by the projection of the preced- 

 ig; penultimate and last whorls arcuately costate, the ante- 

 ior part of the last free, built forward, curved in, the base 

 lardly angular. Aperture vertical, obliquely piriform, peri- 

 stome wanting in the type specimen. Length 16, diam. at 

 10th whorl 8, at penult, whorl 5% mm.; alt. of aperture 4, 

 width 3 mm. (v. Mart.) 



Mexico (Uhde). 



Cylindrella (Holospira) imbricata MART., Monatsber. 

 Berl. Akad. Wissensch., Nov., 1863, p. 540; Malak. Blatter, 

 xii, 1865, p. 15, pi. 1, f. 2, 3. PFR., Monogr., vi, p. 390. 

 Holospira imbricata Martens, FISCH. & CROSSE, Miss. Scient. 

 Mex., Moll., i, p. 336. v. MART., Biologia, Moll., p. 273, pi. 

 16, f. 25. 



"This very distinct species does not appear to have been 

 found by any subsequent collector. It differs from all others 

 of the genus in the short, club-like form of the shell, the 

 greatest diameter being in the tenth whorl ( at about one-third 

 of the whole length, as seen from above) , the following whorls 

 diminishing remarkably in diameter, and the under edge of 

 some of them projecting a little over the following whorl. 

 Fischer and Crosse 's figure of H. gealei resembles it somewhat 

 in outline, but is not so strikingly swollen above, and wants 

 the vertical costae." (v. Mart.) 



