LYMNEIDZ OF NORTH AMERICA. 107 
are somewhat malleated and in a few cases there are a few obscure 
revolving ridges; whorls 7, convex, very slowly increasing in size, the 
body whorl slightly compressed laterally in the majority of specimens ; 
nucleus reddish, flattened; spire very acutely conical, 114 times the 
length of the aperture; sutures deeply impressed; aperture elongate- 
ovate, continuous; outer lip thin on the edge, but thickened within by 
a well marked, heavy varix; inner lip reflected over but not closing 
the umbilicus, leaving a well-marked chink; parietal callus rather 
heavy and tightly appressed; the columella is covered by a distinct 
fold, somewhat resembling a tooth. 
Aperture 
Length. Width. Length. Width. 
19.00 7.00 7.00 4.50 mill. type. 
15.10 6.25 6.00 20 ae cotype. 
13.50 5.50 5.50 2.50 “ cotype. 
Types: Smithsonian Institution, 5 specimens, No. 162721. 
Cotypes: Two specimens Chicago Acad. Sci., No. 23875. 
Horizon: Pleistocene marls. 
Locatity: Marl Lake, Anticosti Island, Canada. 
REMARKS: <Anticostiana is a very distinct species, exactly com- 
parable with no other species of American Lymneid. It has a faint 
resemblance to some forms of desidiosa and also to elongated forms of 
obrussa. It is, however, distinct from both these species. It is probably 
an extinct species, as nothing like it has been seen in the multitude of 
specimens examined during the preparation of this monograph. This 
is undoubtedly the shell mentioned by Bell (op. cit.) as “the most 
abundant species in the shell marl from Marl Lake, Anticosti.” 
Galba bakeri (Walker). Plate IV, figure C. 
Lymnea bakeri WALKER, Nautilus, XXII, p. 18, pl. ii, figs. 11-12, June, 1908. 
“SHELL: Slender, elongate, perforate; whorls 5; spire elongated, 
turreted ; apex acute ; body whorl narrow, elongated, compressed below ; 
suture deeply impressed ; lines of growth fine and regular with fine sub- 
obsolete, revolving, spiral lines; aperture narrow, elongated, within the 
flare of the lip, the sides are nearly parallel, and about equally rounded 
above and below; lip thin, sharp, suddenly and broadly expanded, sub- 
reflected, continuous, not appressed to the parietal wall, and roundly 
reflected over the perforation, columella straight, without a fold; axis 
round and smooth. 
“Alt. 16.5, diam. 7.5, length ap. 8.5, width 4.5 mm.” (Walker). 
Type: Coll. Bryant Walker, No. 9353. 
Horizon: Pleistocene Marls of Michigan. 
Locatity: Pine Lake, Charlevoix County, Michigan. 
