Doyle — Some Researches in Experimental Morphology . 443 



EXPLANATION OF PLATES XXVIII-XXXIV. 



PLATE XXVIIL 



1. Young graft of Pelargonium zonale var. meteor. 



2. Young graft of Phytolacca dioica. Shows method of numbering. 



3. Pelargonium zonale var. meteor, A, 1390, 3/5. A well-grown graft photographed 



on January 7th, 1914, i.e. about eight months after grafting. 



4. The same. A near view of the petiole. 



5. Near view of petiole of Solanum Balbesii, A, 13119, 24/5. Photographed 



June 7th, 1914. 



PLATE XXIX. 



1. Solanum Bichardi, A, 1301, 10/4. Complete plant photographed on June 21st, 



i.e. a little over two months from date of grafting. 



2. P. zonale var. meteor, grafted 6/5/13, photographed 8/1/14 — much reduced, i.e. 



main stem below was about f inch thick. 



3. A leaf of Sanchezia nohilis rooted on which a sprout had been grafted 15/4/13. 



Photographed to show root system 8/1/14. This plant never grew well, 

 mainly because it was not eared for well. 



PLATE XXX. 



1 . Cross-section normal petiole of P. zonale. a - upper, 6 = lower side ; c = 



mechanical ring, x 20. 



2. Central bundle of I. x 45. a = wood ; 6 = part of phloem near wood ; c = part 



of phloem away from wood. 



3. Portion of same to show quiescent cambium remains between a and b of 2. 



x200. 



4. Portion of 2, showing outer phloem mass, x 200, 



