I didn't get a single photo of these in focus, but I think the pictures are clear enough to get an ID. These are near the fence, can't remember if it's the Woodland Garden or the BC Garden. The tubular flowers are small, a little longer than the diameter of the Herb-Robert (Geranium robertianum) in one of the photos. Flower arrangement seems to be a raceme, growing on single-stem plants (?) with square stems. The first photo seems to indicate that they were fairly tall, but I remember them mostly being down at Herb-Robert height. Leaves are as interesting as the flowers, but I can't figure out how to describe them. It makes me think of Apiaceae in structure, except that the flowers are tubular and not in umbels.
Apparently it's not true that the photos are clear enough to get an ID. Do I really see a couple of heart-shaped flowers, with all the rest (and all the ones I saw) turned sideways to look like cylinders? And I'm wondering if those very appealing little leaves have misled me and they are just a young stage of Dicentra leaves. Based on that theory, I would guess Dicentra formosa from the flowers (or D. eximia from the dark flower tips), but Asian bleeding-heart, Lamprocapnos spectabilis, from the leaves. There were plenty of recognizable Dicentra formosa around. For instance, this Dicentra formosa photo is from last week. The plants in question, with the dark flower tips, never struck me as being the same as this, which is why I wonder if they would be D. eximia. Except for the leaves. I'm adding a habit photo of about the same quality as the others.
Wendy, that little plant was bugging me. I knew I had seen it around and was thinking Corydalis. I asked Douglas (Justice) when he last passed my office. Fumaria martinii an exotic from Europe.
Thank you very much, Eric and Douglas! For one thing, I'm pleased to find that my photos and eyesight aren't so bad that I missed recognizing a bleeding-heart. And thank you for including that link, with all those good photos. Common name: Martin's fumitory. It's not a species listed on the Wikipedia Fumaria - Wikipedia page, so quite exotic (I think I'm using the term "exotic" differently from what was said above), but the genus seems to be used in herbal medicine. Papaveraceae family, surprisingly enough to me.
According to Euro+med F. martinii is a synonym of Fumaria reuteri. There seems to be disagreement on the name.
Eric, thanks for that link too. A few more synonyms, and some great common names - zapaticos del Niño Jesús, for one (little shoes of Baby Jesus)! Wikipedia has the F. reuteri name.
I took another hundred or so photos of these fumitory plants, and have a few worth posting. I looked for them again last week and couldn't find them, kind of incredible considering that they range for a stretch of 16 posts along the chain-link fence, inside and outside the garden, both ways from the Robinia pseudoacacia (which is not in bloom yet, though I think every other of these is in bloom in the city). I thought I'd photographed every flower the first time I saw them. Ha! I did that today. The last one has a detail I haven't seen as clearly in the others - the attachment of those wing things in the second upright flower from the left. I should mention again that these flowers are very small, just over 1cm long. I found some excellent photos at Wild Plants of Malta & Gozo - Plant: Fumaria reuteri (Martin's Ramping Fumitory) - they show the wing things (bracts?) very clearly.
There is also a healthy contingent of these on the great lawn near the Pavilion. I was told only a third of the grass gets mowed now on mowing day, so there is probably lots of stuff that hasn't been seen before.