HEY. O. HENSLOW ON THE SO-CALLED SCORPIOID CYME. 511 



On the Origin of the so-called Scorpioid Cyme. 

 By the Rev. George Hen^ow, M.A., F.L.S. 



[Abstract, read November 6, 1879.] 



This paper in fall, with a Plate, will appear in the Society's 

 1 Transactions.' The points of importance to which the author 

 called the attention of the Fellows in the reading of the paper 



may be thus summarized. 

 w He pointed out some errors in deducing the scorpioid from the 



dichotomous cyme, as follows : 



1. Opposite pairs of bracts? being successively in planes at 

 right angles to each other, the resulting sympode would be a 

 volute, and not a helix. 



2. The position of the bracts (when present, as in B or ago) is 

 such that they are not opposite to the flowers. 



3. There are always two rows of flowers, not a single row, as 

 would be the case. 



4. The appearance of a flower in the fork between the two 

 branches of the inflorescence (as in Myosotis) is not usual, and is 

 due to the adhesion between the terminal and the highest axillary 



raceme. 



5. The peculiar arrangement of the flowers has giren rise 

 to the supposition that there is a dichotomy of the apex 

 that while one half continues the axis, the other becomes a 

 flower. The author, however, points out that there is no 



practical difference between the actual condition presented 

 and lateral budding; so that this theory would seem to be 

 superfluous. 



Authors have hitherto confounded " the true scorpioid ra- 

 ceme" (Henslow) with spicate degradations of a sympodial inflo- 

 rescence. 



He (Mr. Henslow) refers it to the indefinite system, and ex- 

 plains its origin by a new principle of phyllotaxis, which he first 

 discovered in Lagerstrcemia, viz. in resolving opposite and decus- 

 sate leaves into alternate, instead of their lying on a continuous 

 spiral line, the line oscillates through three fourths of a circle : 

 and if such a line be drawn from flower to bract, it will represent 

 the so-called scorpioid cyme of the Boraginese. An intermediate 

 stage is represented by the inflorescence of Lathvaa squamaria. 



LINN. JOUBN. — BOTANY, YOL. XYU. 2 P 



