1886-87.] Movement of Water in Plants. 97 



(IG) Van Tiegliem, Aim. d. Sci. Nat., 1871, p. 298; also Text- 

 book, p. 804. 



(17) Darwin and Phillips, Proc. Cam. Philos. Soc, vol. v. pt. v. 



(18) Kohl, Die. Trans, d. Pflanz., Brunswick, 1886. 



(19) Dufour, Arb. d. Bot. Inst. Wurzhurg, 1883. 



(20) Weber, Per. d. deut. Bot. Ges., Bd. iii., 1885. 



(21) Errera, Bull. Soc. Roy. d. Belg., 1886. 



(22) Pfeffer, Physiolog. Pflanzen, Bd. i. p. 127. 



(23) Haberlandt, Physiolog. P-flanzen Ajiat., Leipzig, 1884. 



(24) Westermaier, Ber. d. deilt. Bot. Ges., 1883, p. 371. 



(25) Leclerc du Sablon, Bull. Soc. Bot. d. la France, viii., 1886, 

 p. 208. 



(26) Van Tieghem, Bidl. Bot. d. la France, viii., 1886, p. 132. 



(27) Zimmermann, Ber. d. deut. Bot. Ges., 1883. 



Facts regarding the Mor^liology and Affinities of certain Genera 



of the Order Scrophidariaecoi. By P. Sewell. 



(Read 14th July 1887.) 



Systematists have noticed with considerable detail the 

 different modifications in the flowers of Scrophulariads, and 

 made use of such for the purpose of distinguishing one genus 

 from another. They have, indeed, rather attempted to detect 

 differences than to see resemblances. 



In this way they have somewhat overlooked the natural 

 series of such modifications which afford the most important 

 evidence of relationship and common ancestry. 



The following notes instance a few of these series which 

 have come under my notice in an attempt to determine the 

 relationships of certain genera of Scrophulariaceffi. 



In regard to the gynceeiwn, we may notice that fewer ovules 

 occur in Veronica than in the less speciahsed genera of the 

 order. This reduction, entirely in keeping with the condition 

 of the calyx and corolla, serves as one of many examples that 

 might be brought forward to show that reduction is an almost 

 constant concomitant of specialisation. 



A feature of very considerable interest has been observed 

 and shown by Mr W. E. Fothergill in regard to the placenta- 

 tion. In young ovaries of Digitalis, he noticed that instead 

 of an axile placentation towards the apex, it was very often 

 parietal — suggesting the similar series of modifications in 

 Saxifragete. In Datura, also, the four cells are at times not 

 apparent near the apex of the ovary, where, owing to the 

 cessation of growth in two of the septa, the ovary appears 



TBANS. BOT. SOC. VOL. XVII. G 



