LYCOPERSICUM ESCULENTUM 559 



After this overarching has been accomplished, there is little further 

 individual growth; but the entire basal portion of the calyx ring 

 grows uniformly to form a short cylindrical calyx tube. Each 

 sepal has three to five bundles with fine branches that extend 

 throughout all parts of the lobe. The structure of the calyx lobe 

 is leaf-like and the mesophyll consists of about fifteen layers of 

 spongy parenchyma. The epidermis is covered by a thin cuticle; 

 and numerous stomata occur on the abaxial surface, especially on 

 the tube and at the base of each lobe. The guard cells on the 

 abaxial surface protrude somewhat above the other epidermal cells, 

 while the smaller ones on the adaxial surface are not raised. The 

 calyx is pubescent, producing short, unicellular hairs and longer 

 multicellular ones with a group of basal cells. The glandular hairs 

 are stalked and terminated by a group of four or more cells. (Fig. 

 i9i, £.) Short-stalked hairs and papillae occur on the adaxial 

 surface of the calyx lobes. 



Following the differentiation of the sepals, the continuous 

 circular ridge of the corolla develops from the growing point of the 

 flower primordium centrad to the sepals. On this, the primordia of 

 the petal lobes arise at points alternate with those of the calyx, and 

 their growth results in the formation of the five or more distinct 

 triangular teeth of the gamopetalous corolla. (Fig. r^i., C) 

 Just prior to anthesis, the corolla grows rapidly and pushes the 

 calyx open. (Fig. x^t,, A.^ The epidermis of the corolla is 

 composed of thin-walled cells; and on the adaxial surface near the 

 apex of the lobes, many of them protrude as papillae. Numerous 

 glandular hairs with short stalks occur on the abaxial surface. 

 Stomata are lacking. The corolla lobes are about eight to ten 

 layers in thickness and yellow chromoplasts occur in the spongy 

 mesophyll. 



The stamen primordia arise as the corolla elongates and its 

 undiverged base becomes tubular. They are alternate with the 

 lobes of the petals, and are diverged near the base of the ridge from 

 which the petal primordia are developed. (Fig. 194, D.) This 

 is followed by the growth of the zone basal to the stamens and 

 petals, so that the lower portions of the filaments appear to be 

 undiverged from the tube of the corolla. (Fig. X93, A.') The 

 terminal portion of each stamen primordium develops inde- 

 pendently and at first they are distinct; but, later in ontogeny, the 

 anthers may be somewhat closely appressed laterally. The anther 



