On Spiral Vessels in the Roots of Dicotyledons. Ill 



the Indian Zoology (in t. — .) under the name of O. (Aracana) 

 auritus. On comparison with these species it proved to be 

 very distinct, and therefore I propose for the future to distin- 

 guish it as Ostracion Reevesii. It is much larger than any of 

 the Australasian species. It is regular, granular, with three 

 smooth rather arched bands on each cheek ; in its present dry 

 state it is of a uniform whitish grey colour, and much com- 

 pressed, and higher than the species above described. The 

 rays of the caudal fin are thick. Besides those named in the 

 list there was also sent an Apistes, which appears to be new ; 

 it may be called A. Tasmanensis, Gray: when dry, lead colour, 

 scaleless, suborbital and preopercular spine very long, pro- 

 duced ; middle of dorsal fin with a large black spot ; palatine 

 teeth velvet-like. 



Brit. Mus. Feb. 10, 1838. 



X. — On the Existence of Spiral Vessels in the Roots of Dico- 

 tyledonous Plants. By the Rev. J. B. Reade, M.A., F.R.S. 



To Richard Taylor, Esq. 



Peckham, Feb. 10, 1838. 

 My dear Sir, 



In the few explanatory remarks which I ventured to offer in 

 Philosophical Magazine for Nov. 1837* on the chemical com- 

 position of vegetable membrane and fibre, I had occasion to 

 allude to the existence of spiral vessels in the roots of dicoty- 

 ledonous plants. The attention of English botanists being 

 hereby directed to a statement somewhat at variance with re- 

 ceived principles, I have been requested to furnish a more de- 

 tailed account than the nature of my former communication 

 permitted. I must beg, therefore, to avail myself of your va- 

 luable pages. 



It has been usual to consider spiral vessels as peculiar to 

 the structure of monocotyledonous roots, and as forming a di- 

 stinctive character between the root and the stem of dicotyle- 

 dons ; and so thoroughly has this opinion of their position 

 gained credit, that I have been able in no case to remove it but 

 by giving ocular demonstration that it is in opposition to facts. 



An attempt to trace to their origin the spiral vessels in the 



