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THE NAUTILUS. 15 
perigrapta begin and where does it stop? Any of these varieties is 
just as much entitled to name as is the one selected for this honor. 
Among the rest is a large var., 23 mm., from Lookout Mt., Tenn. 
This variety is almost smooth or very sparingly costate. It is 
slightly wrinkled like Z. inornatus. Butit is crowded with these 
incised lines above and below ! 
Another form that I collected at Gasper, Picking Co., Ga., in 
August, ’83, is very costate, and has the incised lines very much 
crowded and developed. The Lookout shells have the parietal 
tooth long, curving, and joining the columellar callus in the umbili- 
cal region. The Gasper specimens have this tooth short and very 
erect. They also have the lip very much widened, and the spire ele- 
vated. I have, in my suite of this species, four shells, taken at ran- 
dom from a lot collected at Murphy, Cherokee Co., N. C., in every 
one of which the wpper tooth is well indicated, the parietal tooth is 
short and erect, the spire elevated, the body whorl obtusely carinate 
and the whole surface above and below is crowded with “ microscopic 
spiral incised lines.” Now which is perigrapta? The deep cost 
and the multitude of spiral incised lines roughen the epidermis of 
the Morrowville examples and begin to introduce the conditions 
attaining in swbpalliata. These shells, in consequence, have a some- 
what dull appearance, while the Lookout Mt. and Cherokee Co. spec- 
imens are highly polished. 
A variety from Braden Mt., Tenn., is heavily costate, and has the 
spiral lines (as has every shell of appressa) but not “ incised.” 
These shells range from 12 mm. to 25 mm. (my largest specimen of 
sargentiana). ‘This last form is costate, has the erect tooth, the cari- 
nate body whorl, and the spiral lines, not “ incised,” and is in fact 
nearer to the typical appressa, in every aspect, than the highly 
polished and shining specimens from N. C. 
Now what is the philosophic method in treating such a problem ? 
Is it to give all these varieties names, loading up our literature and 
check lists with trinominal designation for varieties that differ in the 
same County of the same State? Or shall we write our labels ap- 
pressa var. with locus and so on to the end? There is at least one 
collection in the U.S. where the latter method prevails and will to 
the end. I am tempted, in this place, to prune and reset Mr. Pils- 
bry’s phylogenic tree according to my ideas, but I will not take 
space for so doing now. I do not, however, believe that dentifera is 
the root or that the branches sargentiana, appressa and perigrapta 
