PLATE 28 



167 



169 



170 



166. Ipomcea coccinea. Transverse section; petiole of mature leaf equidistant from the lamina and the base. 



167. Ipomaea quamoclit. The same. 



168. I-pomoea sloteri. The same. 



169. Ipomcea coccinea. Multicellular protuberances at base of petiole. 



170. Ipomcea quamoclit. The same. 



171. Ipomcea sloteri. The same. 



