530 MacDougal : Symbiosis and Sapkophytism 



14. Reinke : Zur Kenntniss des Rhizomes von Corallorhiza und 

 Epipogon. Bot. Zeit. 56: 145. 1873. 



15. Thomas: The genus C^ra//W«'2<2. Bot. Gaz. 18 : 166. 1893. 



Hxplanatiou of Plates 



Plate 367. (l) Entire specimen of Cephalanthera Oi-egana Reichenb : A, base 

 of aerial stem. (2) Premorse x\^\zo\nQ o'i Corallorhiza Arizouica : A, X^xxmx^zS. bud; 

 B, B, B, B, scars of preceding buds ; C and D, offsets from which arise coralloid 

 branches. (3, 4 and 5) Coralloid branches of Corallorhiza Arizonica. (6) Typical 

 specimen of Calypso borealis : A, young corm ; B, corm of previous season's forma- 

 tion. (7) Aberrant specimen of Calypso : A, o\A. corm with coralloid branch. (8) 

 Widely aberrant form of Calypso : A, young corm ; B, old corm with large coralloid 

 branch, C. 



Plate 368. Corallorhiza Arizonica Wats, (i) Longitudinal section of tip of old 

 coralloid mycorhiza : a, a, epidermis ; 6, />, medio-cortex, containing disintegrating 

 branches of fungus ; <r, stele ; m, m, permanent mycelium ; d, d, branches ; e, leaf. 

 (2) Portion of transverse section of mycorhiza : ^, epidermis ; r, permanent mycelium; 

 w, internal branches in medio-cortex ; /, inner cortex; b, phloem; 0, xylem. (3) 

 Cells from cortex: a, a, hyphae of permanent mycelium ; c, masses of hyphae in medio- 

 cortical cells ; n, n, n, nuclei of cortical cells. (4) Hyathode from premorse rhizome. 

 (5) Stomata from coralloid branch. (6) Section of epidermis of coralloid branch 

 showing structure of stoma : e, ^.epidermal cells; a, guard cells; «, nucleus. (7) 

 Transverse section of aerial stem : e, epidermis ; c, cortex ; (/, sclerenchyma sheath ; 

 X, X, fibrovascular bundles. 



Plate 369. Cephalanthera Origana Reichenb. ( i ) Transverse section of stele 

 of storage root : /, medulla ; x, x, xylem ; c, endodermis. (2) Transverse section of 

 stele of fibrous root : v, passage cells of endodermis ; e, thickened cells of endodermis 

 outside of phloem; s, phloem; z, xylem; c, medulla. (3) Longitudinal section in 

 stele ; 0, s, vessels ; vi, medulla ; n, endodermis. (4) Portion of transverse section of 

 rhizome : e, epidermis ; h, cortex ; /, sclerenchyma sheath ; g, fibrovascular bundles 

 with heavy sheath ; r, parenchyma. (5) Stoma from leaf. 



