102 THE NAUTILUS. 



Barren Brook Bog, in Caribou, is covered by vegetation ; but the 

 Lovely Brook Bog is wet, dangerous and difficult to approach, ex- 

 cepting in one place. 



I have just received from Mr. Bryant Walker a paper upon the 

 " Shells of the Marls of Huron County," reprinted from the Geo- 

 logical Survey of Michigan, Vol. VII, part II, pp. 247-252, in 

 which comparisons are made with specimens from Aroostook county, 

 Maine. To my knowledge there has been no extensive list pub- 

 lished of the shells found in the marl deposits of Maine, and no 

 comparison made with the living species in the same localities. 



Samples of marls have been sent to me from Presque Isle, Lime- 

 stone, California Town, in New Brunswick, Canada, and other 

 places. The most abundant species are Limntea desidiosa, Planorbis 

 parvus and Pisidium contortion? in all the localities. 



Possils in the Marl of Barren Brook Bog. 

 Vertigo sp. Fragments only. 

 Succinea obliqua Say. Rare. 

 Succinea ovalis Gld. Rare. 

 Physa heterostropha Say. Rare. 

 Limnaaa desidiosa Say. Abundant. 

 , Planorbis trivolvis Say. Common. 

 Planorbis companulatus Say. Rare. 

 Planorbis bicarinatus Say. Rare. 

 Planorbis parvus Say. Abundant. 



Planorbis (?). One specimen related to P. crista Lin., probably 

 a new species. 



Ancylus parallelus Hakl. Two specimens only. 

 Valvata sincera Say (?). Not common. 

 Anodonta fragilis Lam. Rare. 

 Sphaerium simile Say. Rare. 

 Spha^rium rhomboidium Say. Rare. 

 Calyculina securis Prime (?). Rare. 

 Pisidium adamsi Prime. Few. 

 Pisidium compressum Prime. Few. 



1 Dr. V. Sterki has kindly examined all the Pisidia in my collection. Some, 

 of the specimens are still held by him, pending the receipt of more material 

 for comparison with specimens from other parts of America and Europe. I 

 am under the greatest obligations to him, and also to Mr. Bryant Walker, for 

 valuable information. 



