Screw

Screw (Bostryx) is a certain form of inflorescence . Below the terminal flower of the main axis there is only a minor axis closed off by a flower, which continues to drive a minor axis with a flower either to the right or to the left.

The screw is derived from the dichasium in that only one is formed instead of two side branches. If the side axis appears alternately to the right and left, it is called a wrap .

Screw
Screw, schematically from above
Potato ( Solanum tuberosum , screw with concealment )

One variant is the double screw . This has the first branch on both sides of the main axis and others like a simple screw.

Double screw
St. John's wort ( Hypericum perforatum )

source

Strasburger, E. et al .: Textbook of botany for universities . 15th edition, Jena Verlag by Gustav Fischer 1921, pp. 114, 488

Individual evidence

↑ Strasburger, E. et al .: Textbook of botany for universities . 35th edition, Spektrum Akademischer Verlag 2002, p. 168

[1] Strasburger, E. et al .: Textbook of botany for universities . 35th edition, Spektrum Akademischer Verlag 2002, p. 168