38 AMERICAN JOURNAL 



3. Helicogena hortensis, Mull. 



Dr. Beck writes in his MSS. about this species : " Wormski- 

 old has told me that he has found on the leaves of the small 

 shrubs of Salix lanatus, in the vicinity of the interior of the Gulf 

 of Tgaliko, a banded snail not unlike our garden snails. Two 

 years ago (1844 ?) I obtained a dead specimen from Greenland ; 

 probably introduced." It is certainly found alive in Iceland. 



4. Achatina, sp. 



" Mr. Beverly communicated to me an Achatina, which he 

 found on an island in Baffin's Bay ; and as it is a tropical genus, 

 I cannot refrain from noticing so extraordinary an occurrence." 

 Leach, Thompson's Annals of Philosophy, 1819, xiv, p. 203 

 (Journal de Physique, 1819, p. 465). As Leach does not men- 

 tion the specific name, it is probable that it was a species unknown 

 to him. Perhaps it was Fusus Norvegicus, or some other marine 

 shell resembling Achatina. 



5. Unio Groenlandica, Fer. 



Die breite Mahlermuschel aus Greenland, Schroter, Flusconch., 

 p. 181, t. ix, f. 1. 



Unio G-roenlandicus, Schrb't., on the authority of Ferussac, 

 Lea, Obs., vol. ii, p. 151. 



Unio sp. Middend. Reise, p. 395. 



The shell represented by Schroter is Unio testudinarius, Spgl., 

 (U. marginalis, Lam.), a common shell from Tranquebar and 

 other places in British East Indies. 



6. Mya ( Unio) tenuis, Schroter, Wiedemann, Archiv fiir Zoolo- 



gie und Zootomie, 1802, 2 Bd., 2 Stuck, p. 107. 



Is stated to be from the rivers in Greenland ; "If zoll. long, 

 3 J zoll. breit." A variety is stated to be J zoll. long, 3^ zoll. 

 breit. Although the measures look erroneous, it is probably 

 a variety of Unio testudinarius, Spgl. 



7. Anodontites radiata, Val., Enc. Meth. 1824, p. 147, t. 203, 



f . 4 ; it is Modiolaria nigra, Gray. 



Moller was anxious to know if larger bivalves were found in 

 the lakes and rivers of Greenland. I have found the following 

 observations in Moller's diary about this question : 



" The most lakes contain snow-water, pure as crystal ; no bul- 

 rushes, not even confervas. Not a single living being breathes 

 there, except a solitary Colymbus glacialis." 



