E. sericeus stems collected 26-30 September 2012 [Hays Co.].
To test the visibility of the distinctive basal acrodromous venation of E. sericeus with glabrous upper leaf surface (east of the Trans-Pecos in Texas) 7 plants/stems (shown above) were collected from diverse habitats at Purola Preserve (Hays Co.) and their leaves were examined with a dissecting microscope. The results are given in the table below. Of the 99 leaves examined, the basal venation was apparent with just over half. 4 leafs showed only 1 lateral vein. With one plant with 16 leaves, 'C', no secondary veins were visible.
The stems were then scanned with light through the leaves and with this method all leaves revealed the expected venation; e.g., to see this for stem G above; and to see this for stem F above (not tabulated).
| Stem ID |
Number of leafs |
Lateral ven. not visible |
Basal ven. clear |
Basal ven. very faint |
Only 1 lateral vein |
Pinnate veins on upper half |
| A | 14 | 4 | 3 | 4 | 3 | 1 |
| B | 7 | 3 | 2 | 2 | 0 | 0 |
| G | 10 | 1 | 7 | 2 | 0 | 0 |
| H | 14 | 4 | 3 | 7 | 0 | 0 |
| I | 16 | 13 | 0 | 2 | 1 | 0 |
| C | 16 | 0 | 13 | 3 | 0 | 1 |
| D | 22 | 17 | 0 | 5 | 0 | 0 |
| Totals | 99 | 42 | 28 | 25 | 4 | 2 |