AMPULLARIA CRASSA, VAR. 47 
NOTE I. 
ON A NEW VARIETY 
OF AMPULLARIA CRASSA SWAINSON 
FROM FRENCH GUYANA 
BY 
Dr. J. H. VERNHOUT. 
(With figs. 15 a, b on Plate 2). 
The Gonini-Expedition, that explored in 1903 and 1904 
some of the rivers, giving origin to the Marowijne or Maroni, 
as it is called by the French (see sketch of Surinam on 
p. 2 of this volume), made also a little excursion on 
French territory, and explored a part of Mount Cottica on 
the right bank of the Lawa. Here, at an altitude of 450 M., 
were collected some specimens of Doryssa hohenackeri Phil., 
of which species, although recorded from Surinam in 
general, no well-stated locality in our colony is known 
(see p. 35), and also three specimens of an Ampullaria, 
which apparently is related to the A. crassa Swains. from 
the Lawa, mentioned in my paper on the non-marine 
molluses of Surinam (this volume pp. 1—46). With Mr. 
Sowerby, who had he kindness to compare it, I am 
agreeing in taking it for a variety of this species. 
AMPULLARIA CRASSA Swains., var. MONTICOLA noy. var. 
(Pier, hep. 19 db). 
The shell is distinguished by its aperture being shorter 
and wider than in the typical form, and by its smaller size. 
Length (decollated) 23, diam. 22!/,; length of aperture 
17'/,, diam. 13 m.M. 
Notes from the Leyden Museum, Vol. XXXVI. 
