Correction

Looks like when I was looking up info online about that White Icicle Radish I got confused. The White Icicle is not a Daikon, but a similar looking spring radish. Thank you Ira Wallace at SESE for the heads up. SESE sells seeds for both kinds of radishes, and in an earlier post from Sept. 27th you can see an illustration of Daikon, also called Myashige. Here is a bit from one website about the two:
There are two different types of Radishes; the spring Radish, which is commonly used in salads, and the Oriental [daikon] or winter Radish, which isn't as well known, but is becoming more popular.
Spring Radish (R. sativus) - This hardy annual loves cooler weather. It forms small rosettes of rough, dark green leaves and enlarged, edible roots. The foliage may be mixed and cooked with Turnip or Mustard Greens when it is young and tender. Young spring Radishes are ordinarily eaten raw, before they become pithy or pungent with age. There are several different kinds, which vary in color and shape. Some are oval, cylindrical, round, or tapered like an icicle. Each type has a wide range of colors; white, red, white and red, pink and white or a combination of white, rose and purple.
Winter Radish (R. sativus variety longipinnatus) - The winter Radish is also known as the Oriental Radish and Daikon. Winter Radishes aren't regularly grown in the U.S., although many of the old standby winter varieties have been grown for decades by experienced gardeners. The name comes from the practice of gathering the roots in the winter.
- taken from http://www.botany.com/raphanus.html