269 



consistency and do not become agglutinated so rapidly as in. 

 the other species. As in the latter, the external members 

 of the lower series are the first to become softened by absorp- 

 tion of stigmatic fluid, the others usually remaining un- 

 influenced and retaining their form until they are released 

 from the matrix and fall into the stigmatic-cavity. 



The tendency in the genus Phajus to produce supple- 

 mentary anthers or staminodia is well known. Three such 

 cases were observed in the material under examination. The 

 staminodes took their origin from the upper shoulder of the 

 wing and represent the suppressed lateral anthers of the 

 inner whorl. 



EXPLANATION OF PLATE XXII. 



Fig. 1. Column of P. Bernaysii from the front, the anther 

 is in the horizontal position; dehiscence has taken place. 

 a, anther ; st, stigma, ap, stigmatic appendage ; w, wing of column ; 

 u\, origin of staminode ; p, pollen-mass of 2nd series showing 

 below rim of anther. 



Fig. 2. The anther has been removed together with the 

 upper series of pollinia. Two pairs of pollinia belonging to the 

 lower series can be seen, their bases still resting in the clinandriunu 

 Lettering as in fig. 1, with the addition of : a 13 point of attach- 

 ment of anther to back of column. 



Fig. 3. A vertical mesial section of column, anther and pollinia 

 removed; lettering as before with the addition of: st.c, stigmatic- 

 canal; cl, clinandrium. 



Fig. 4. Anther from below showing the two pairs of pollinia 

 of the upper series. One pair is detached, showing the convex 

 and plane surfaces of the masses and their acute apices. Lettering 

 as in fig. 1, with the addition of : p 1? pollen-mass, showing convex 

 surface; p 2 , pollen-mass showing plane surface; i, retracted 

 integuments. 



Fig. o. A vertical section through the upper part of column, 

 the anther and upper series of pollinia removed. Dehiscence has 

 taken place and a pair of pollinia belonging to the lower series 

 may be seen with their bases resting in the clinandrium, their 

 apices having slipped down against the margin of the stigmatic 

 appendage. Lettering as in the preceding figures. 



Fig. 6. Gynostemium of Diuris longifolia from the front 

 showing : ap, anther-point ; w, wing of anther-filament ; st, 

 stigma; rd, rostellar-disc. 



Fig. 7. Same from the back. Lettering as in preceding 

 figure, with addition of : a, anther. 



Fig. 8. Same from the side, showing separate origins from 

 the receptacle of anther-filament and the style of the stigmatic- 

 plate. The wings of the filament have been removed, a, anther; 

 ap, anther-point; f 1} anther-filament; /,, stvle of the stigmatic- 

 plate; st, stigma; r, rostellum; p, pollinia. 



Fig. 9. Stigmatic-plate from behind with pollinia attached 

 to viscid disc of rostellum. The anther and its wings have been 

 removed, st.p, stigmatic-plate; r, rostellum; p, pollinia. 



