334 Durand: Marchantia polymorpha 



Fig. 42. One peripheral cell divided transversely. 



Fig. 43. All peripherals divided transversely. 



Figs. 44, 45- Peripherals and mother-cell of axial row divided transversely, the 

 latter ,nto the central cell and mother-cell of the neck-canal-cells. The young arche- 

 gomum is now differentiated into the neck and venter. 



Fig. 46. Transection of venter M this stage. 



Fig. 47. Transection of cover of same archegonium as in figure 46. 



Hgs. 48-54. Steps in the radial division of the wall and increase in length of the 

 archegonium. & 



FK* 55, 56. The neck-canal mother-cell has divided transversely into two. 



h.f !a /' ^ COndhi ° n in Which the ventral canal-cell has been cut off 



before the formation of four neck-canal-cells. 



Fig. 58. Four neck-canal-cells, central cell undivided. 

 • * ig. 59. Transection of venter of about the stage of figure 58. 

 *IG. 60. Transection of neck of same archegonium. 



p£ L J 6 "? 1 ? U diVided int ° the e ^ and ventr ^ ^anal-cell. 



F r fir m' , , eg ° niUm enlargin ^ ; four «eck-canal-cells. 

 F G. 65. Nuclei of two of the neck-canal-cells divided. 



F G. 66. Transection of neck of about the stage of figure 65. 



' %■ potion of cover-cells of same archegonium as in figure 66. 



cells whi, . ArChe , g ° nmm mature i canal-cells ready to disintegrate ; five neck-can.1. 

 cens witti seven nuclei. 



Fig. 69. Base of archegonium, egg ready for fertilization. 



Sporogonium 



the boning IZfopZ^^ C ° ntaiDing * ***** ** -*"« ** *" 

 Fig. 71. Transection of similar stage. 



Firs 77 So i7 if ° f arche gonmm. 



Fig 8, t ^ diVidCd int ° <* Uadrants - 



*io. 81. Transection of quadrant stage. 



the wall'of the w^T" ^ "^ ****' In 8l and 8z note the P ericlinal divisi ° D iD 



*3. 85-87 show fl u eP l Sh0 u Wing formation of anticlinal walls in each octant. Figures 

 Pseudoperi, th and ^ ^^^^ * ** - + »~* 

 Figs' !i ' o 9 ?' ^f nSections of similar stages. ' 



FIG. 9rEmbryo!nc e r; b,70S -- ^ the S,ight increase in size over 7* 

 and the pseudoperianth. '" ***' N ° ,e the massive base of the archegonium 



halvesbein'gse^lXX^nV^ 1 ^ ** ^ stains more deeol* *e wo 

 Fig 96 Simila I transverse wall. 



the proximal' pal™' ZnbTl\ ^ T? ^^ ^^ Staining P° rtion is not se P arated ^ 

 Fig. 97 An olde 1 ° ngInal trar »sverse wall. 



tiated into an outer IZ\ of^ ^ '" Whi ° h the d '" Stal half of the embr y° iS differen " 

 tissue within, and the baS™ yer ° f ce,ls enclosing the deeply staining sporogenous 



*«* at the base of the S^^~jJ* haS h ^ » «"" "^ * 



