Comparative elevation of Testacea in the Alps. 57 
cornuto, et ad apicem dentibus duobus acutis, alteroque infero trun- 
cate, armatae, intus ciliatae : maxillce et organa labialia ut in Geotru- 
pidibus typicalibus : antennce longiores, 1 1-articulatse, articulis 2, 3, 
4, subaequalibus : thorax magnus, transversus, lateraliter et postice 
elevatus, depressione magna subrotundata, partem anticam thoracis 
occupanti, in qua ad marginem anticum, tuberculum parvum longi- 
tudinale exstat ; margo ipsius partis depressus ad latera, subacutus, 
postice vero depressus ; angulis posticis thoracis productis subacutis : 
elytra semiglobosa, valde convexa, nee striata nee oculo nudo punc- 
tata, tenue marginata : pedes robusti, tibiis anticis 6-dentata. 
The remarkable outline of this insect, with its dentate mandible, 
subelongated antennae, carinated head, singularly depressed thorax, 
and smooth gibbous elytra, seem to be characters of higher value 
than those indicating a species. I have not, however, ventured to 
separate it generically from Geotrupes, but have figured the essen- 
tial organs for comparison. G. latus of Leach, figured by Sturm in 
his Catalogue, and said by Dejean to be from Barbary, seems to 
be allied to this species, but wants the remarkable characters ex- 
hibited by the head and thorax of G. lethroides. 
V. ' -On the Comparative Elevation of Testacea in the Alps. By 
EDWARD FORBES. 
THE influence of elevation on the distribution of plants is at pre- 
sent a popular theme with the botanist, whilst the same influence 
on that of animals is comparatively neglected, though (among the 
invertebral tribes particularly) many important results may be ex- 
pected from researches on that subject. The following data, though 
few, may yet have their use in showing how far such an influence 
affects the species of shell-bearing mollusca. The stations at which 
the observations were made are the Pass of the Gemmi, and the 
mountain of Faulhorn in the Swiss Alps, during the month of July 
1835. The highest part of the Gemmi is that beside the Dauben- 
see, marked by Keller at 6360 feet. The summit of the Faulhorn 
is 8200 feet above the sea-level. In the absence of accurate mea- 
surements, I have marked the distribution by the characteristic 
plants of the elevations at which the species were found. 
I. The highest Testacea occurred at the edges of glacial masses by 
the Dauben-see, and on the Faulhorn at about 7000 feet. Vege- 
tation that of "the Glacial Zone :" Soldanella alpina and minima, 
