On a collection of 
Gammariis from Randers Fjord, Denmark. 
By 
K. Stephensen. 
(('.omimiiiicMtions from tlu* Department of Arthropocls of Ihe Zoological Museum, 
Copenhag'en. — No. 2). 
With 9 figures. 
((’ommuuicaled al Ihe meeting on Xovl)r. 24lh 
Among a considerable material of Invertebrata from Randers 
Fjord, collected by Dr. A. C. Johansen and Mr. Hj. U s s i n g, with 
a view to showing the variation of the fauna from the mouth of 
the fjord to the head, especially in regard to the salinity^), a 
great many specimens of Gaminarus were also found. The mate¬ 
rial contained the following species: G. pulex L., G. lociisla L., G. 
Zaddachi Sexton (new to Denmark), an intermediate form between 
G. lociista L. and G. Zaddachi Sexton, thus showing that G. Zad¬ 
dachi is not a good species, and G. Diiebenii Lilljb; (new to Den¬ 
mark). Thus there were all the species hitherto known from Den¬ 
mark except G. marinas Leach, but in return two „species“ were 
new to Denmark. 
As the salinity in the fjord varies from 0%o in the inner parts 
to 24 %o at the mouth at the bottom and 18 %o at the surface, 
the species vary a great deal according to the environme^t. 
The following pages will serve to show that also the specific 
characters are so vague that it is most probable that all the species 
in reality are one species. 
Already 1877 in his paper Crustacea . Daniæ (Naturhist. 
Tidsskrift, ser. 3, vol. 11, 1877, p. 123) Meinert considers G. 
Duebenii and G. marinas varieties of G. lociista ; but his reason 
h This paper, with the title „Randers Fjords Naturhistorie, ved Dr. A. C. 
Joh an se n“, is now going to the press. 
