3 8o 



MORPHOLOGY OF MEMBERS, 



shoot of the system is called the Sympodium or Pseud-axis. It consists, in 

 Fig. 136, B, of the pieces between i and 2, 2 and 3, 3 and 4, 4 and 5 ; the weaker 

 terminal portions of the respective branches i, 2, 3, &c. are bent sideways. A 

 comparison of Fig. 136 C with A shows that between a sympodially developed and 

 a spurious dichotomous system the only point of difference is that in the latter each 

 branch produces two stronger lateral branches. If in C one of the branches is 

 imagined to be suppressed alternately left and right, the form A results, which is 

 then easily transformed into B. 



Sympodial systems occur in two different forms, according as the lateral 

 shoots, the basal portions of which form the pseud-axis, arise always on the 

 same side or on different sides of it. 



Fig. 136.— Cymose branching's represented diagrammatically ; v4, 5 scorpioid (cicinal) cynje ; Cdichasium; Z> helicoid (bostry- 

 choid) cyme ; the numerals indicate the order of succession of the lateral shoots which spring from one another. 



If the sympodial ramification takes place always on the same side — e. g. always 

 to the right, as in Fig. 128, Z>, or always to the left — the whole system is called a 

 Helicoid Cyme ^ or Bostryx ; if, on the other hand, each branch which continues 

 the system arises alternately right and left, as in Fig. 136, A^ B, the system is 

 a Scorpioid Cyme or Cicinus. If in these cases we have to do with leafy shoots 

 where the leaves are arranged spirally, a more exact definition of the terms right and 

 left becomes needful. It is then necessary to imagine a median plane drawn through 



* [Some difficulty will perhaps be felt with regard to Fig. D, which stands for a helicoid cyme 

 in the text, but which is also identical with the scorpioid cyme of descriptive botany, and corresponds 

 to the specific name ' scorpioides'' given by Linnaeus to several plants in which it occurs. The term 

 scorpioid was introduced by A. P. De CandoUe (Organographie, vol. I. p. 415), to express a unilateral 

 cyme the undeveloped portion of which is usually rolled up. This is the characteristic inflorescence 

 of Borraginese, amongst which Myosotis has long been distinguished as ' scorpion-grass ' on this 

 account. Bravais (Ann. des Sci. Nat. 2nd ser. vol. VII. p. 197) distinguished the helicoid cyme, 

 which he defined as having the successive flowers ranged in a spiral round the pseud-axis. He 

 amended De Candolle's definition of the scorpioid cyme by pointing out that the flowers are in two 

 rows parallel to the pseud-axis,] 



