Source: http://kanoh.tokyo/nihon/style/style_time/style75tubushi.html
Japanese Hairstyles: Historical Overview Part 02: Women’s Hairstyles of the Edo Period, Part 03
Hairstyle Name: Tsubushi Shimada (つぶし島田) lit. “Crushed Rice Paddy Island”
This hairstyle is a variation of the Shimada-mage established during the Tenpo period (1830-1844 CE) in the Edo era. It was a huge trend at that time especially between yuujo and brothel owners. There;s no cushion at the root of the tail, so the tail appears to have been “crushed.” Such a style was recognized as “iki,”or chic, and considered the opposite of the “taka-shimada.”
It was widely popular among all women of Japanese society. The lower base of the topknot, giving it the appearance that it has been crushed, is what gives this style it’s name. Enhancements to this topknot, in the form of kanzashi, kanoko and chirimen, would help to identify the age and status of the wearer.