ABSTRACT
This work aims at determining genera through seed characteristics found in ninety-nine species studied.
We have discovered a variation not only in the shape but also in the structure of the testa and in the amount of seeds per capsule.
On the basis of shape and structure, twelve types of seeds have been established, besides the five ones previously named by Thieret.
We have then observed that the Gratioleae is the tribe that possesses the greater number of types, including the reticulate-honey-combed, the honey-combed (alveolate), the longitudinally furrowed, the furrowed-undulated-Tetraulacium and the granulate one.
In the genera which makes up the Gratioleae, there is a predominance of the reticulate type, that occurs in Bacopa Aubl. (f.1-20), Mecardonia Ruiz et Pav. (f. 20-25), Stemodia L. (f. 28 and 34), Otacanthus Lindl. (f. 35-37), Lindernia (f.41), Scoparia L. (f.44-46), Achetaria Cham, et Schlecht. (f.47). Capraria L. (f.48), Gratiola L. (f.49), Mazus Lour. (f.50). Then after that there is the longitudinally furrowed one, found in two genera Stemodia L. (f. 26,28,30-32) and the Limosella (f. 52).
Among the Gratioleae, the Stemodia L. is the genus that presents the greater variability of types: it prossesses the granulate (f. 25,29,33), the reticulate (f.28 and 34) and the longitudinally furrowed (f. 26,27,30-32).
Then there are Verbasceae (retlculate-honey-combed), Calceolarieae (longitudinally-furrowed, f.56) and Hemimerideae (reticulate-crested, f. 57-67), all of them with only one genus.
The Antirrhineae tribe, represented in Brazil by four genera, has served as the basis of five types of seeds, for the two species of Antirrhinum L. have varied suficiently and have allowed, each one, the creation of one type (f. 68-69). Thus, we have the types granulate-retlculate-winged (f.68), the dense-muricated (f.69). The undulated - winged Linaria (f. 70-70a), the thick-barked-crested-Cymbalaria (f.71) and the crested-winged Maurandia (f. 72).
We then arrived at the Digitaleae, with one genus only, the Digitalis L. which possesses the reticulate type (f.73).
The Veroniceae, with Veronica L., have given rise to the creation of two types: the marginated-scooped (f. 76) and the pseudo-laevis (f.74,75-75a and 77).
The Buchnereae have the inflate-reticulated type as predominant, as it occurs in Gerardia L. (f.85-87), Nothochiius Radlk. (f.90), Castilleja L. (f.91). Melasma Berg. (f. 92), Alectra Thunb. (f. 93-94), and Escobedia Ruiz et Pav. (f.95). The reticulated found in Buchnera and Anisantherina (f.84) and the linear-oblong-Physocalyx type (f. 96-97)
As to the number of seeds per capsule, they vary from a little (less than 20) in Veronica L. Tetraulacium Turcz. and Cymbalaria Hill, to relatively numerous in Angelonia H.B., Antirrhinum L., Linaria Mill. Digitalis L., Bacopa Aubl., Mecardonia Ruiz et Pav., Stemodia L. and to very numerous ones (over 300 seeds) in Melasma Berg., Alectra Thumb., Escobedia Ruiz et Pav. and Physocalyx Pohl.
A correlation has been established among the many types of seeds, starting from the honey-combed type, and arriving at the reticulate and thence, reaching the most adapted ones under the idea that any adaptation to the anemocoria should be a degree of development reached at by seeds.
We could establish a criterium of differentiation only using the seed-character for the creation of a "key”.
The problem has been arisen as to the Anisantherina Pennell being a synonym for Rhamphicarpa Benth. emend. Engler, and such a problem would only be solved after the examination of species related to the genus Rhamphicarpa.