5°6 
AMERICAN JOURNAL OF BOTANY 
[Vol. 10 , 
Table i. Length {in microns) 'of adjacent fusiform initials in random samples of the lateral 
meristem of old stems 
Non-stratified Gambia 
Gymnosperms 
Species 
Max. 
Ave. 
Min. 
Ginkgo biloha L... 
3,000 
4,000 
4,200 
3,000 
5,000 
8.700 
7.700 
4,400 
5,000 
4,100 
2.200 
3.200 
3,300 
2.200 
4,000 
6,600 
6.800 
3.200 
3.800 
2,900 
1.400 
2,300 
2.400 
1,000 
2,500 
4.200 
4.100 
2.200 
2,300 
2.100 
Pinus Strobus L.... . 
Picea Abies (L.) Karst.... 
Juniperus virginiana L..... 
Larix decidua Mill.... 
Sequoia sempervirens Endl.... 
Agathis robusta F. M. Bailey... . 
Tsuga canadensis (L.) Carr. 
Podocarpus Nageia R. Br. 
Cedrus libani Barrel. 
Average........ 
4,9io 
3,820 
2,450 
Dicotyledons 
.A. Vesselless 
Trochodendron aralioides Sieb. et Zucc... 
6,200 
4,500 
O-i 
Oi 4* 
O O 
O O 
2,800 
2,400 
Drimys Winteri Forst.. 
Average....\. 
5,350 
3,850 
1 
2,600 
B. Vascular tissues not highly differentiated 
Betula populifolia Marsh... 
1,160 
1,620 
2,300 
1,500 
1,700 
2,300 
1,700 
1,400 
1,400 
1,100 
940 
1,310 
1,900 
1,100 
700 
990 
1,200 
Myristica philippensis Lam. 
Altingia excelsa Noronha. 
Liriodendron tulipifera L. 
700 
1,100 
Urandra luzoniensis Merr.... 
1,400 
1,600 
1,300 
1,100 
Dillenia philippinensis Rolfe.. 
1,000 
Gordonia Lasianthus L.... ... 
1,000 
Cornus florida L.... 
800 
Symplocos tinctoria L’Her... 
1,100 
600 
Halesia diptera L.. 
900 
800 
Average. 
1,620 
1,260 
890 
C. Vascular tissues highly specialized 
Carya ovata (Mill.) C. Koch... 
600 
* 520 
420 
Litsea glutinosa C. R. Rob...... 
700 
550 
390 
Prunus serotina Ehrh... 
590 
460 
320 
Excoecaria Agallocha L...... 
870 
630 
410 
Mangifera monandra Merr..... 
830 
570 
390 
Acer rubrum L...... 
610 
490 
320 
Garcenia dulcis Kurz... 
1,020 
740 
520 
Vatica Mangachapoi Blanco..... 
810 
610 
4 10 
Barringtonia racemosa (L.) Roxb.... . 
900 
720 
500 
Psychotria luzoniensis F. Vill...... 
1,080 
700 
450 
Average..... 
800 
600 
410 
