Study of a Tulip (Ammirael Winckel), c. 1645. Pieter Holsteyn II (Dutch, c.1612-1673). Brush and watercolors in crimson, grey and green over traces of charcoal on antique laid paper; sheet: 31.9 x 21.3 cm (12 9/16 x 8 3/8 in.). This image of a tulip was made as part of a tulip book used as a growers marketing tool during the so-called tulip mania, a speculative bubble in 17th-century Holland when ten tulip bulbs could cost more than a stately Amsterdam canal house. The striations on the tulip, which were caused by a virus in the bulb, made it especially valuable. Pieter Holsteyn II was one of many artists in the Netherlands at the time who specialized in botanical illustration. This tulip's Dutch name, inscribed on the sheet, translates to "Admiral Winckel." Winckel was the family name of one of the largest growers of tulips in the period.