The actual value of a rhythmic mark in D’ni music is absolutely dependent on the meter in which it appears. 
This is perhaps the most difficult leap for us to make; the same rhythmic mark may indicate different pitch durations in different systems, sometimes even within the same measure.
D’ni rhythm is most easily understood as splitting into two families: duple and triple. The duple family is based on a full vertical stroke, while the triple family is based on a full horizontal stroke. 
Smaller cross-strokes indicate subdivisions of the two- or three-beat full stroke. While it is perhaps easiest to transcribe D’ni duple rhythm in 2-count as 2/4 and triple rhythm in 3-count as 9/8, transcribing triple marks quickly becomes unwieldy. It would be better if we could escape the fundamentally duple Western rhythmic notation system and transcribe triple marks such that three “quarter” notes make one whole note, three “eighth” notes make one “quarter” note, etc.
Duple marks do not only occur in 2-count meters, triple marks only in 3-count meters, however. Marks from one family can be borrowed in the opposite meter to indicate what would be tuplets in Western notation. Simply put, duple marks indicate a duple subdivision in 3-count, and triple marks triple subdivision in 2-count.
In the classical meters, great care must be exercised when interpreting rhythm. The 2 portion of each metric cycle will use duple marks, the 3 portion triple marks. Tuplets can, of course, occur as well. An excerpt from music written in queen’s meter prominently displays this quality, with the 3 portion in green and the 2 portion in purple:
As seen above, rhythmic marks are often combined; there is no strict stacking order for such complex rhythms, but clarity and compactness are always considered. Important divisions in the metric cycle (downbeat and, for classic meters, midbeat) are always reflected in rhythmic notation, and smaller duration marks appearing in complex rhythms tend to be grouped with the preceding or succeeding marks that complete the subdivision, as in the third and fourth notes above.
