144 THE NAUTILUS. 
considerable divergence among the species. Other biologic 
notes and information on the ecologic relations of Cerions are 
given. 59 plates fully illustrate the material. 
Dr. Bartsch’s experiments clearly have important bearings 
upon systematic zoology as well as upon the doctrine of evolu- 
tion generally.—H. A. P. 
MoLLusca OF THE CROCKER LAND EXPEDITION TO NORTHWEST 
GREENLAND AND GRINNELL Lanp. By Frank C. Baker (Bull. 
Amer. Mus. Nat. Hist., Vol. 41, pp. 479-517, pls. 25-27, Dec., 
1919). An interesting review of some of the arctic mollusks, 
especially of the Buccinidae of which Buccinum tanquaryt and 
B. ekblawi are described as new. 
FRESH-WATER MoLLuscA FROM COLORADO AND ALBERTA. By 
Frank C. Baker (Bull. Amer. Mus. Nat. History, Vol. 41, pp. 
527-539, Dec., 1919). Planorbis similaris, Physa smithi and 
Galba alberta are described and figured as new. 
NEw SHELLS FROM THE NorTHWEsT Coast. By William H. 
Dall (Proc. Biol. Soc. Wash., Vol. 32, pp. 239-252, Dec., 
1919). Ten new species and varieties and a new genus Pantel- 
laria (type Megerlia monstruoga Scacchi) are described. 
LOCOMOTION IN TWO SPECIES OF THE GASTROPOD GENUS ALEC- 
TRION WITH OBSERVATIONS ON THE BEHAVIOR OF PEDAL CILIA. 
By Manton Copeland (Biol. Bull., Vol. 37, pp. 126-138, 1919). 
THe CentTRAL NERVous SysTtEM oF NucuLA AND MALLETIA. 
By W. A. Hilton (Jour. Ent. and Zool., Vol. 11, pp. 75-78, 
1919). 
New Species OF MoLLuscA FROM VARIOUS DREDGINGS TAKEN 
OF THE Coast oF NEW ZEALAND, THE SNARES ISLANDS AND THE 
Bounty Istanps. By Miss M. K. Mestayer (Trans. and Proc. 
N. Zealand Inst., 1919, Vol. 51, pp. 130-135, pl. 8). Lnotra 
suturi, Orbestella hinemoa, Crossea cuvieriana, Leucosyrina thomsont, 
L. cuvierensis and Vepecula cooperi are described as new. 
