174 MOLLUSCA. 
himself 2! treats S. strebeli as synonymous with the N.-American 8. labyrinthica (Say). 
The pretended identity with the allied EKuropean eocene and pliocene forms is refuted 
by Sandberger, Land- und Siissw.-Conch. der Vorwelt, 1870-75, pp. 277, 726. 
2. Strobila salvini, (Tab. X. figg. 1, 1 a-c.) 
Helix salvini, Tristram, P. Z. S. 1863, p. 411°; Pfr. Monogr. Helic. Vivent. v. p. 334”. 
Helix (Fruticicola) salvini (Tristr.), Fisch. & Crosse, Miss. Scient. Mex., Mollusca, i. p. 260°. 
Testa latiuscule umbilicata, trochiformis, angulata, fulva, supra oblique costulata, infra laevigata, laminis 
tribus spiralibus perlucentibus; spira conica; anfr. 53, vix convexiusculi; apertura sat obliqua, lunaris, 
peristomate incrassato, breviter refle xo, paries aperturalis plica intrante subobliqua munitus. 
Diam. maj. 3, min. 24, alt. 14-2 millim. 
Hab. N. Guatemata: Mountain-forests of Vera Paz (Salvin 1-8), 
An inspection of the typical specimens, kindly lent me by Canon H. B. Tristram, 
enables me to give a fuller description of this species, which proves to be nearly allied 
to S. labyrinthica (Say). ‘The riblets of the upper surface cross the angle of the peri- 
phery and extend a little way on the lower face of the shell. The umbilicus occupies 
about one third of the diameter of the shell, whereas in S. /abyrinthica it occupies only 
about one fifth of it. 
The internal lamelle are in this species about the same as in S. labyrinthica, accord- 
ing to the description given by E. Morse and the figures contained in Binney’s works. 
Two whitish spiral lamellz are visible from outside at the base, shining through the 
shell, more distinctly in young shells than in full-grown ones, because in those the 
shell is thinner; they are situated really on the upper side of the lower wall of the 
last whorl. Two others, situated on the lower side of the upper wall or ceiling (parietal 
lamelle), are to be seen by looking into the aperture of a not full-grown shell; the 
uppermost, or that nearest the suture, is the longest, extending even somewhat beyond 
the limit of the aperture in the observed specimen, the following one is shorter and lies 
more beneath—it corresponds to the third of S. labyrinthica in the above-mentioned 
figures. A corresponding lamella to the second of S. labyrinthica is not visible in the 
specimens of S. salvini, probably only because it does not come so near to the aperture 
and I would not break the only shell which exhibited clearly those lamella by seeking for 
it. Under an ordinary lens these lamelle show also in S. salvini the repeated swellings 
described by Morse. In fragments of S. labyrinthica from Florida, examined for com- 
parison by myself and Dr. Hilgendorf, under a higher magnifying-power, the swellings 
appear to be somewhat less regular, and composed of more scattered and shorter points 
than in the said figures. 
