1892. } The Seed Coats of Malvacee. 35 
It appears as a continuous pellucid band (fig. 1 /.) across the 
outer end of the palisade cells. In the Leguminosae this was 
noticed, at least as early as 1838, by Schleiden and Vogel."! 
The nature of this light line has been studied by a number of 
investigators. Quite different views have been taken in regard 
to.10. 27 
Russow,!* after investigation, comes to the conclusion 
that the cell-wall is more compact and contains less water a 
this place. Sempolowski!* is of the opinion that it may be 
due to a differentiation in the molecular structure of the cell- 
walls. Lohde,'5 who studied carefully the development and 
structure of the seed coats of some Convolvulacee and Mal- 
vacez thinks that it arises from the cuticularization of small 
Immediately under the palisade cells are two layers of 
roundish cells of dark brown color. The number of integu- 
ments in the different species studied is the same, and the 
number of layers of cells in each integument is practically 
the same. 
ALTH&A ROSEA Cav.; fig. 1.—In specimens of A. rosea 
the outer integument, a 6, has both layers of cells developed, 
the outer layer, a, being developed rectangularly in a tangen- 
tial direction. This layer gives rise to the epidermal out- 
Stowths, or seed hair. The next layer, 4, is nearly isodiametric. 
"*VoceL : 1. c. Vol. xix uu, taf. xi, fig. §5, 58; taf. xiv, fig. 77, 80. 
eh Acta der Leop. Car. Fee iehis —- aS = 
9. MATTIROLLA: La linea lucida nelle cellule Malphigiani degli ge ed 
menti seminali, Mem. della R. Acc. delle Sc. di Torino. Ser. I, ol. 
seit See abst. Just’s Bot. Jahresb., 1885. p. 825. : 
Russow : Vergleichende Untersuchungen tiber die Leitbundel-Kryptoga- 
a Pp. 32. St. Petersburg, 1872. 
Leipaig: 189 : Beitrege zur Kenntniss des Baues der Samenschalen, p.11, 
, 4. 
1g LOHDE : - C., P. 30, 36, 
/UNowicz: Die Lichtlinie in den Prismenzellen der Samenschalen, p. 3, 
p. # +P. 17. Prag, July 12, 1877. oe 
Gunther Beck; Vergleichende Anatomie der Samen von Vicia und Ervum, 
PP. 32. Sitzb. d. k. Akad. d. Wissensch. Band txxvi. I. Abth. Mai Heft. 1878. 
