61 

 DESCEIPTION OF PLATES. 



Plate VI. 



Dipodiuvi punctatum, Br. 



Fig. 1. — Column from the front, x3 — a, hemispherical, lid-like 

 anther; /■. rostelliim ; 5, stigma. 



Fig. 2. — Column from side, x3. 



Fig. 3. — Column and labellum from the side (x3), showing — 

 col, column; (/, anther: I, labellum (middle lobe); ic, lateral lobes, 

 of labellum, embracing column on each side of stigma. 



Fig. 4. — The same seen from back of column. Lettering as in 

 fig. 3. Note the hairy landing stage on tip of labellum. The- 

 hairs are directed inwards towards the column. 



Fig. 5. — The top of the column and rostellum, fix)m a bud, 

 just before expansion. The anther with its contained pollen-masses 

 has been removed, showing — d, the disc developed from the ros- 

 tellum and overhanging the stigma; c, the false caudicle or 

 "stipes," developed also from rostellum, and growing backwards 

 from the disc; f, a triangular tongue of tissue rising in a sickle- 

 shaped eminence between the stipes. This is quite short in the 

 young bud, but gradually grows backwards until it unites with 

 the back of the column ; he, back of column ; s, stigma. 



Fig. 6. — Stigma very much enlarged, showing — dep, the little- 

 depressions in its floor into each of which a pollen-mass is subse- 

 quently deposited. 



Fig. 7. — The labellum seen from the top (x3), showing — ml,. 

 the middle lobe with its hairy tip ; w, the lateral lobes. 



Fig. 8. — The same seen from the side. 



Fig. 9. — Column Avith labellum in position. Half the 

 labellum has been removed by a longitudinal section. Note its close 

 contact with the middle third of the column, just below the bevelled 

 portion of the latter, so as to show the triangular space in which 

 are situated the stigma and disc — t s, triangular space ; col, 

 column; a, anther; /■, rostellum; ml, middle lobe labellum, 



Plate VII. a. 



Prasophyllum gracile. 



Fig. 1. — A side view of the column, showing the anther-case 

 retracting, thus liberating the two pollen masses, which are 

 attached to the rostellum by a strap-like caudicle — a c, anther-case; 

 p, pollinia ; c, caudicle; r, rostellum and disc; lap, lateral 

 appendages of column ; s, stigmatic surface. 



Fig. 2. — More complete retraction of the anther-case has 

 alloAved the pollinia to spring out and assume a horizontal position 

 behind the rostellum. This is the second stage in rotation. Let- 

 tering as in fig. 1. 



Fig. 3. — Represents the third stage in rotation of the pollinia. 

 They are now vertically over the rostellum. Lettering as in fig. 1, 



Fig, 4. — Complete rotation of the pollinia has taken place, and 

 they are now adherent to the centre of the stigma, but still 

 attached to the rostellum by their disc. The lateral appendages in 

 this and the next figure should have been shown longer. Lettering 

 as in fig. 1. 



