Rannaigheacht bheag (ran-á-yah voig)

A traditional Irish quatrain of 7-syllable lines [7/7/7/7] (‘old-school’),
 or 8/6/8/6, ending in 2-syllable words all linked by consonance
(in its old meaning, ‘having the same vowels’),
 with at least two cross-rimes in each couplet
 (can be consonance in first but should be rime in second)
and alliteration in every line, which in the second couplet
 must be between the last two stressed words in each line,
and with the dunedh, of course (ending in the same word, phrase,
 or line it began with).
Poem ExampleRon-a’yach Rhyme
Writing rhyming words, giving
living lines, fit for fighting
biting boredom while living
in style with witty writing.
(c) Lawrencealot – May 16,2012
Visual Template
As with the other Irish forms, a template can show you the syllable count and a bit more, but cannot be definitive as so much variation is possible while meeting the formal  requirements.
In the example below some words not hi-lighted could have been as serving one or more rules.

Séadna (shay'-na)

Séadna is:
    1. written in any number of quatrains.
    2. syllabic 8-7-8-7.
    3. written with L1 and L3, 2 syllable end words; L2 and L4, 1 syllable end words.
    4. rhymed. L2 and L4 end rhyme, L3 rhymes with the stressed word preceding the final word of L4. There are two aicill-rhymes in the second couplet.
    5. composed with alliteration in each line, the final word of L4 alliterating with the preceding stressed word. The final syllable of L1 alliterates with the first stressed word of L2.x x x x x x (x a)
      x a x x x x b
      x x x b x x (x c)
      x b x c x x b

Many thanks to John Clitheroe for his work on the PoetsGarret site.

Séadna (shay’-na):
A quatrain stanza of alternating octosyllabic lines with disyllabic endings and heptasyllabic lines with monosyllabic endings. Lines two and four rhyme, line three rhymes with the stressed word preceding the final word of line four. There are two cross-rhymes in the second couplet. There is alliteration in each line, the final word of line four alliterating with the preceding stressed word. The final syllable of line one alliterates with the first stressed word of line two.
B x x x x x (x a)
x x x x x x b
x x x x c x (x c)
x b x c x x B
Caring for the watercolor
I find you looking at me there
Blush to white palor, dim valor,
Thus, where its blue core had found care.
Kathy Anderson
Example poem
Fight on Poet
Fight on against fear of failure;
cure your weary will and fright.
Pursue dreams; ignore cause killing
themes, write– winning thrilling fight.
(c) Lawrencealot – July 4, 2012
Visual Aid
  
This is my 2nd attempt to write specs for this form.  It is without a doubt the most demanding poetry form I have encountered.  Since it is not possible to make a template that is much more than the equivalent of house plans on a napkin, handed to an architect…I have included the check list I referred to repeatedly while writing this one verse poem.
Besides being overly challenged for a long while; I chose a one verse poem so I could demo the Line 4 2nd word rhyme, and the first-last unity.
Enjoy…this form will help fight off dementia.