182 
The Ohio Naturalist. 
[Vol. VII, No. 8, 
Martynia louisiana Mill. 
Ruell’ia strepens L. 
“ strepens micrantha (En- 
gelm & Gray) Britt. 
“ ciliosa Pursh. 
Triosteum perfoliatum L. 
angustifolium L. 
Gnaphalium decurrens Ives. 
Anthemis cotula L. 
Woodsia obtusa (Spreng.) Torr. 
Dennstaedtia punctilobula (Michx.) 
Moore. 
Phegopteris hexagonoptera(Michx.) 
Fee. 
Tofieldia glutinosa (Michx.) Pers. 
Cypripedium acaule Ait. 
reginae Walt, 
caudidum Willd. 
hirsutum Mill. 
Cypripedium parviflorum Salisb. 
Peramium pubescens (Willd.) 
MacM. 
Explanation of Plate XIII. 
Fig. 1. Cross section of leaf of Xanthoxylum americanum Mill, 
showing position and character of a normal internal gland. 
Fig. 2. Cross section of leaf of Xanthoxylum americanum showing 
an unusually large gland. 
Fig. 3. Longitudinal section of gland of Xanthoxylum americanum. 
Fig. 4. Cross section of leaf of Boebera papposa (Vent.) Rydb., show¬ 
ing internal gland. 
Fig. 5. Cross section of leaf of Hypericum prolificum L., showing 
position and character of internal gland. 
Fig. 6. Longitudinal section of gland of Hypericum prolificum. 
Fig. 7. Section of leaf of Glecoma hederacea L. showing external 
scale. 
Fig. 8. Cross section of leaf of Gaylussacia resinosa (Ait.) T. and G., 
showing position and character of an external secreting scale. 
Fig. 9. Section of scale of Gaylussacia resinosa, showing central 
stalk cell. 
Fig. 10. Glandular hair of Urtica dioica L. 
Fig. 11. Glandular hair of Cypripedium reginae Walt. 
Fig. 12. Glandular hairs of Corylus americana Walt. 
