Fig. 11.3-2. Transverse section of delphinium stem (Delphinium ajacis). The outermost layers of this cortex have differentiated as a hypodermis, which is fairly common. An unusual feature here, however, is that the hypodermis is basically an aerenchyma it has so many large intercellular spaces that it appears to be only loosely attached to the epidermis and the rest of the cortex.