ESMARK : MOLLUSCA OF NORWAV. 99 



8 mill. In Thelemarken the pearls have a beautiful reddish 

 lustre. From Lofoten our museum has received mussels, but 

 they contained only small monstrosities of pearls. 



As the investigations of our land and freshwater moUusks 

 altogether are but very few, it is a matter of course that our 

 literature contains but very little information as to them, even if 

 we take into consideration all the books containing some informa- 

 tion on the subject. 



Strom, Hans. — Det Throndhjemske Videnskabs - Selskabs 

 Skrifter, 1765. 'Only speaks of some few land snails'. 



— Physick og oeconomisk Beskrivelse over Fogderiet 



Sondmore, 1762. 

 Fabricius, J. Chr. — Reise nach Norwegen, 1779. 'Speaks 



of a few naked snails.' 

 Friele, Joachim. — Norske Land og Ferskvands Mollusker i 



Omegnen af Christiania og Bergen, 1853. 



Martens, E. von. — Ueber die Binnen-mollusken des mitt- 

 leren und siidlichen Norwegens Malak. Blatter, 1857. 



— Gesellschaft naturf Freunde zu Berlin, 1881. 



Jensen, Olaf. — Indberetning om en i Sommeren 1870 fore- 

 tagen Reise i Christiania og Christiansand Stifter. 

 Nyt Magazin f. Natiirvidensk, 1872. 



Westerlund, Dr. C. A. — Fauna Suecige, Novegiaeet Danise, 

 1873- 



— Sveriges, Norges, Danmarks og Finlands Land och 

 Sotvattens Mollusker Excursions fauna, 1884. 



Bougemont, M. de. — Bulletin d. 1. Societe' des Sciences nat. 

 d. Neuchatel, xi. 1878. 



Esmark, Birgithe. — Bidrag til Kundskaben om Udbredelsen 

 af Norges Land og Ferskvands Mollusker.. Nyt Mag. 

 f Naturvidensk, xxv. vol., 1880. 



— Nyt Bidrag til Kundskaben om Norges Land og 

 Ferskvands Mollusker. Nyt. Mag f Naturvidensk 

 xxvii. vol., 1882. 



— Die Pisidien des Sudlichens Norwegens. Malak. 

 Blatt. N. F. V. vol. 



— Land and Freshwater MoUusks in the Arctic Regions 

 of Norway. Tromsd Museums Aarshefte, 1883. 



