Photo by] IE. Step. 



FIG. 657. FIELD HORSETAIL (Equiaetum arvenae). 



The barren fronds which grow to a height of two or three feet present a strong contrast to the fertile spikes shown 



on the previous page. Here there are whorls of long, jointed branches from base to summit. NORTH EUKOPE, NORTH 



ASIA, NORTH AFRICA, the HIMALAYA, and NORTH AMERICA. 



515 



