Question
I live in Connecticut and I found a 3 leafed plant(leaves about 12" long) among daylilies.  It has a green pod with white spots about 1/2 way down plant the size of a plumb.  Is it poisonous? I have cats.  I took a picture of it so I could ask around.  Hope you can help.

Answer
Barbara,

The plant in the picture is "Jack-in-the-Pulpit", Arisima triphyllum.  It is one of the more desirable wild flowers.

The flower, which you apparently missed, consists of a hollow leaf like bract with a curved tip (the pulpit) that bends down over an inner cluster of almost microscopic flowers,(Jack).  

What you have there is a cluster of fruit that will eventually ripen and turn bright red with a single seed inside each individual fruit.

While all parts of the plant are poisonous, so are a lot of the other plants that we grow as house plants and landscape plants.  Pets rarely eat them.

Hope this helps,

John