198 21. ORCHIDEiE. Plend.ph. 



A. Pollen longitudinally divided ; caudlcle luith a 

 relinacle. 



a. Retinacle bursicidale, siiigle and common to loth the 

 pollen masses. 



Perigoniimi galeate ; Up long, linear ; 

 lase with a short scrotiform spur .... Loroglossum. 135. 



Perigonium gsXeoXei Lip long, linear; 

 lase flat, or very slightly gibbous Aceras. 136. 



Perigonium galeate; lip spurred; 

 claw bearing 2 scales longitudinally . . . Anacamptis. 137. 



b. Retinacles hursiculate^ 2. 



Per. arched or galeate ; lip spurred ; 

 hiirsicles undivided Orchis. 138. 



Perig. spread; lip spurless, convex; 

 rostellum split into 2 bursicules Ophrys. 139. 



c. Retinacles naked. 



Perlgon. arched; lip spurred, 3-cut; 

 spur bristlelike; rosteUum split Gymnadenia. 140. 



Perigon. galeate ; lip spurred, 3-cut ; 

 spur short ; rostellum split Entaticus. 141, 



Per. arched or galeate; lip spurred, 

 undivided; cells of the anther distant; 

 rostellum Platanthera. 142, 



Per. nearly bellshape ; inner sepales longest ; 

 Up many-cut, purselike at the bottom . . Herminium. 143, 



B. Pollen longitudinally divided ; retinacle 0. 



Per. connivent below; lip enclosed, 

 spurless, undivided; pollen unarmed .... Goodyera. 144, 



C. Pollen granular ; anther 1, 



Per. oblong, connivent; Up obovate; 

 gynizus rather elliptic; sp'kt spiral .... Spiranthes. 145, 



Pf-r. globose, connivent; lip obcordate; 

 gynizus rather elliptic; ste?n leafless Neottia. 146. 



Per. globose, connivent; Up linear, 2-parted; 

 g7jnizus nithev e\\\\^Uc; stem 2-iea\-ed . . .. Listera. 147. 



Per. erect, connivent; Up embracing, entire; 

 ovary sessile; roslellum Cei-halanthera. 148, 



Per. spread ; lip spread, interrupted ; 

 ovarv Y)Gdice\]ed ; rostellum on ihe a^ex Epipactis. Ii9, 



