On the Staminal Hairs of Thesium 
BY 
M. F. EWART, B.Sc., 
University College , London. 
With Plate XVI. 
I N the Genus Thesiunt and in several allied Genera of the 
Natural Order Santalaceae there occur, associated with 
the stamens, curious groups of hairs. These have from time 
to time received the attention of morphologists, who have 
discussed their homology, but no account has yet been given 
of their precise structure and significance. It is proposed to 
fill this lacuna by a narration of the facts gathered from an 
examination of a large number of species of Thesium , and of 
such other genera of Santalaceae as possess hairs of the same 
character. Their service in the mechanism of the flower will 
be considered, and their morphological value briefly discussed. 
Fig. 9 (a longitudinal section of Thesium alpinum ) shows 
the position of these hairs and their relation to the anthers 
in a well known species. The stamens are inserted on the 
simple epigynous perianth-tube, they are equal in number 
to the lobes of the perianth and are opposed to them. The 
hairs arise immediately behind the stamens. 
Character and Position of the Staminal Hairs. — Two varieties 
of these small yellow hairs, or ‘ staminal hairs ’ as I shall call 
them for distinction, are to be found in the genus Thesium : — 
[Annals of Botany, Vol. VI. No. XXIII, October, 1892.] 
