Thank you all for your comments and especially Joe for quoting the original source. For what it's worth, the only online database I know that includes chromosome counts is http://www.tropicos.org/ but it is hardly complete. On 6/25/12 1:40 PM, Tim Chapman wrote: > Some comments: to start the info I looked at shows 12 for both polystachya and speciosa. The reference for speciosa was more recent. This illustrates one of the main issues with counts. It's rare to find a complete list of numbers in a genus all determined by the same method and by the same researchers. Most compilations are incomplete and reflect varying numbers by different researchers etc. If the group you are looking at has B chromosomes then the older reports are often even more variable. > > As to the other quoted parts. With the 12x12 species crosses you've done it would seem there are natural barriers in the way. Unfortunately this is very common (makes sense in the wild, but to a hybridizer this is just a stupid concept!). Your 12x24s are probably tetraploids and it would n