Another angle. Should I cut this fruit off now? Has anyone seen this before?

I think too little or too much water?

Looks like blossom end rot; mostly caused by a fungus, for which you can treat with a fungicide. It is also, at times a sign of Calcium deficiency; add a little gypsum to your soil.

I dont believe that the soil is lacking calcium, tho I am no expert! I fertilized it with Espoma's Citrus-tone last month, which has calcium, and this month I gave it a liquid feed of half seaweed and half BioThrive Grow, which also has calcium. I have also used the liquid seaweed as a foliage feed once this month.

I have a bottle of Garden Fungicide by Safer Brand. Active ingredient is Sulfur. Would this work against Blossom End Rot on my Meyer? I use this on my cherry tree for powdery mildew.

Should I cut this fruit off? Would it be edible?

I read that the fungi make spores - should I be worried about the other lemons becoming infected? I would hate to lose this whole harvest! I have been waiting so patiently!

The tree may have been over watered in the last few weeks, but not drastically so. I will space the waterings out this month to be sure its not being over watered.

Cut that infected lemon and eat it; it should be fine inside.
Blossom end rot is a fungus that infects the fruit at the bud stage; but is not seen until the fruit begins to ripen. The time to treat is at the bloom stage.

The damage you see is not transmittable to the other fruits.

Perhaps brown rot?

See this
http://www.ipm.ucdavis.edu/PMG/GARDEN/FRUIT/citrus.html

Here is a link that might be useful: citrus at UC

It's an oddball lemon, use it like you would a normal lemon.

I cut the fruit and took a look inside. I didnt end up eating the lemon, will post pic so you can see why. When I cut it open there are small white speckles in the center pulp. I cut it up into several wedges, but they all had white speckles inside.

Common sense told me that it didnt look normal (looked like small patches of white fungus growing), so I decided not to eat it. Right choice? Was it ok?

Will the seeds be alright to harvest, wash and plant? Id like to start a project for my young cousins to propagate my tree.

Looks very much like stylar end rot that is more common in Bearss/Persian limes.

I agree that the inside looks bad to me; I wouldn't eat it either. I have an old Meyer Lemon that never looked like that. I do fertilize mine at least several times during the year with both granular and liquid kinds.

It will be interesting to see what the rest of the fruit looks like. I know mine are ripe when they get vey orange and are less firm.