336 MOLLUSCA. 
vulgaris, C. Pfr., which more nearly resembles S. undulata than any other Mexican 
form of this genus. 
Var. moerchi. (Tab. XIX. fig. 8.) 
Succinea moerchi, Dunker, in Paetel’s Catalog d. Conchyl.-Samml. ii. p. 366 (1889) (sine descr.)’. 
Shell smaller, but remarkably thick, very distinctly wrinkled, whitish, with a yellow hue near the aperture ; 
columellar margin thickened, enlarging upwards and passing over into a callous deposit on the upper wall 
of the aperture. About 2 of the whole length occupied by the aperture. 
Long. 14, diam. 9; apert. long. 9, lat. 6 millim. 
99 15, 99 8 5 39 ] 0, 9 6 99 
Hab. Cenrran Mexico: Zimapan, State of Hidalgo (David, in the late Dunker’s 
collection). 
To judge from the thickness, the strong wrinkles, the dull coloration, and the smaller 
size of the shell, this form is probably found in dry unfavourable localities. One 
specimen appears to have been broken near the aperture, probably by falling from a 
shrub, and has been restored in an irregular manner; another has two strong thickenings 
somewhat before the aperture, showing that the growth has been interrupted twice for 
some time at these spots. 
This variety resembles S. luteola, var. rudiuscula, but may be distinguished from it 
by the more inflated shell and the deeper, more oblique suture. 
5. Succinea colorata. 
Succinea undulata, var. colorata, Fisch. & Crosse, Miss. Scient. Mex., Mollusca, i. p. 657, t. 27. 
figg. 5, 5a, 6}. 
Testa oblongo-ovata, solidula, leviter ruguloso-striata, nitidula, griseo-flava, apice intensius colorato (rubes- 
cente); anfr. 3, vix convexi, sutura non profunda; apertura 2 totius longitudinis paulo superans, acute 
ovata, paulum obliqua, intus concolor, nitida, striata, margine columellari levissime arcuato. 
Long. 12, diam. 7; apert. long. 10, lat. 6 millim.!. 
” 11, ” 7; ” 83, ” 5 9 
» 10, ,, 6; ” 8, 55 4, 
” 7, 95 93 ” 5, » 4 5, (young). 
Hab. S.E. Mexico: State of Tabasco (Dr. Berendt!); San Juan Bautista in Tabasco 
(H. H. Smith). 
More resembling the European 8. pfeifferi than 8. putris; distinct from S. undulata 
in the much less convex whorls and weaker wrinkles. Fischer and Crosse describe 
the colour as reddish-rose in the two upper whorls, and pale fallow-yellow in the 
last whorl. The specimens from San Juan Bautista have no distinct red on the upper 
whorls, but only a little darker yellowish-brown hue; the measurements of the largest 
of them is given above in the second line, those of a younger one in the third line. 
