LECT. X.] POSITION OF LEAVES. 537 



The position is termed opposite (opposita),(6.) when 

 they appear directly on opposite sides of the stem, 

 in pairs; and when these alternately cross each 

 other they are said to be decussated (decussa- 

 ta), (7.)- The position is ternate (terna), when the 

 leaves stand by threes around the stem, on 

 the same plane of the horizon ; and quaternate 

 (quaterna) when in fours ; which, however, is not 

 applicable when the four leaves, lying in the plane 

 of the horizon, point towards four opposite di- 

 rections, the term cruciate (cruciata seu crwa*- 

 formis), 8, being employed to denote this posi- 

 tion. When the number of leaves grounding 

 the stem or branch exceed four, and point to 

 different directions, forming a starlike figure, 

 the position is termed whorled (verticillata seu 

 stellata), (.). In the majority of instances the 

 term whorled is used without any reference to the 

 number of rays; but in large natural genera, as, 

 for instance, Galium (Bed-straw), it is necessary 

 to designate these, and for this purpose the terms 

 quina, sena, octona, &c. are employed. When, in- 

 stead of being in pairs, leaves stand solitarily on the 

 stem or branches, spreading in various directions, 

 the position is termed alternate (alterna), (10, 

 page 538); and in this state they form either a 

 spiral line around the common axis (spiralia), as 

 in the Norway spruce fir, Pin us Abies , or are 

 irregularly scattered (sparsa); or they are two- 



