PLATE 29 



172. Ipomoea coccinea. Upper epidermis, limb of corolla. 



173. Ipomoea quamoclit. The same. 



174. Ipomoea sloteri. The same, showing larger cells than in either /. coccinea or /. quamoclit. 



175. Ipomoea coccinea. Lower epidermis, limb of corolla showing slightly wavy cell walls. 



176. Ipomoea quamoclit. The same, showing very wavy cell walls. 



177. Ipomoea sloteri. The same, showing waviness between that of the two parents. 



