Tho Systematic position of thè Bangiacew 
by 
T. Johnson 
Professor of Botany, Royal College of Science, Dublln. 
In November, 1891 I read before thè Royal Dublin Society a pa* 
per entitled a Callosities Niioph7/llu?n versicohr Usirv.)) in which 
I gave an account of thè results of ray examination of thè peculiar 
marginai tubercles of this rare Red Alga. In this paper I stated that 
a magnifìed cross-section of thè callosity shewed vertical rows of 
cells, regularly arranged, as if thè cells in each row had a common 
origin. I also stated that thè structure of thè callosities had an impor- 
tant hearing on thè question of thè mode of constriiction of thè Flo- 
ridean thallus, and on thè systematie position of thè Bangmcece, .a 
group of Red Algae which Schmitz, for various reasons, proposed to 
exclude from thè Florideae. My paper called forth a vigorous criti- 
cism from Schmitz of such a nature as to necessitate a reply on my 
part. Schmitz 's criticism of my observations on N. versicolor is 
based, to a great extent, on a rnisunderstanding or misreading of ray 
statements. Thus my observation (p. 156): I bave not been able to 
raake out any definite layer of cells from which thè cells of thè row 
[of thè callosity] may take origin. Apparently thè thickening takes 
place from within- i. e. [apparently] thè youngest cells are most in- 
ternai- is interpreted by Schmitz to mean that I think consequently 
T. Johnson : Proc. R. D. S. (N. S.) voi. 7. 
2) Fr. Schmitz: Kleinere Beitriige zur Kenntniss der Florideen IMII. (La 
Nuova Notarisia, serie IV, 1893). 
