276 Ewart. — On the Staminal Hairs of Thesium . 
The staminal hairs of other genera closely allied to Thesium , 
e. g. of Osyridocctrpos and Thesidium seem to differ very 
slightly from those already observed. They are in both these 
cases very slender and directed upwards, and although the 
basal cushions are not very distinctly defined in Osyridocarpos , 
the constrictions and rounded terminal cap at the free end are 
particularly clear. In the male flowers of Thesidium and in 
Comandra the perianth hairs are attached to the top of the 
anther — in Comandra so strongly that they cannot be removed 
without breaking. 
In Arjona the character and arrangement of the hairs is 
slightly different. They are short and thick, and spring from 
various levels behind the stamen, forming a column covered 
by short upwardly directed hairs. The cuticle of the hair has 
pronounced spiral markings, and constrictions occur at inter- 
vals throughout the whole length of the hair, giving it a 
decidedly septate appearance. The free ends are not attached 
to the top of the anthers, for only the highest ones attain to 
that level. 
In Quinchamalium , the flower of which is otherwise very 
similar to that of Arjona , no staminal hairs are present. 
I have not been able to find any very satisfactory figures of 
the staminal hairs in Thesium. The best are those of T. 
pratense , by Nees 1 , who correctly shows their appearance and 
position behind the stamens, and of T. stelleroides and T. 
aureum , by Jaub and Spach 2 , where the hairs are well shown, 
attached to the tops of the anthers. There is also a small 
diagram of a longitudinal section through the flower of T. 
alpinum in Engler and Prantl’s £ Pflanzenfamilien ’ (Santalaceae) 
which correctly indicates the position of the hairs in that 
species. In other cases they are represented as springing 
from a common vertical axis which originates behind the 
stamen (see figures of T. linophyllum and T. ebracteatum by 
Reichenbach 3 ; of T. midticaide by Ledebour 4 , &c.) ; but I 
have not been able to find any examples of this arrangement. 
1 Gen. Flor. Germ. 1835. n. 48. 2 111 . pi. Bot. t. 104, 300. 
3 Iconogr. Bot. 1827. 4 Ic. FI. Ross. t. 237. 
