This is a seclection of the movies I got, showing representative streches of development. I'll note the most interesting points of each one. I have other movies that may show other nuances and for each movie, I have a second focal plan, which usually shows other useful information.

Generally, I think H. scutatum represents an exageration of "standard" urodele development, though there are some interesting questions in this regard. A blastopore lip that starts broadly dorsal and then gets smaller dorally and doesn't really become complete ventrally is pretty typical so far as I can tell; H. scutatum even shows a faint ventral lip in one movie. The biggest question is "where is all that stuff going through the blastopore going?", especially laterally. Is it ingressing ("subducting" as in salamanders and newts), or are the bottle cells re-expanding inside the BP? I actually did a little microsurgery on one of them and learned a few things: 1) the outermost intact layer you left me with is still some kind of jelly coat; it's not easy to remove, but more do-able than most of the newts I've dealt with. Inside this is a very thin/feeble vitelline envelope that comes off fairly easily. I tried culturing one devitellinized embryo in a clay well; it wasn't happy. I did a dorsal isolate from another, and that appeared to be doing fairly well the last time I looked, before it rotted or I lost track of it. I think I could use this kind of explant technology to look for subduction or other types of ingression. This is a fairly interesting evo-devo question (to me anyway). I could probably also get a better start-to-finish BP closure movie that would show the progression of things a bit more clearly. The thing is, it would be ideal to have a few days advanced notice, so that I can reserve the scope for a long time. The other thing that I don't need the fancy scope for would be a lateral view movie; these can be very nice for getting a more comprehensive view of morphogenesis, including correlating epiboly with BP closure.

I'll try to get a disc out to you before too long, but I've been really swampped. I can trace morphogenesis backwards to get a crude fate map, if this is of interest.

Let me know if you have trouble with any of the movies; you'll need quicktime to view them. Some of these movies are quite large (20MB), so will take some time to download.

The movies are all at 10 minute intervals; the first two are 12 frames per second (so two hours per second), while the last three are 20 frames per second (or 3:20 per second).


This movie nicely shows the formation of the blastopore. The area that contracts into the blastopore is pretty amazing.

epi 04a 12 fps


Shows immense amounts of involution through the BP, both animally and vegetally.

epi 08a 12 fps


Nice view of later BP morphogensesis. Shows the feeble ventral BP (about 13:00, first time); shows the onset of BP inversion, about 17:00, which appears to result from the formation and addition of the posterior neural folds to the flat blastopore slit (although that's a huge area, and perhaps only the more lateral parts of it are truely neural; much of the initial upward curving lip actually involutes, or something); shows what I would consider the end of gastrulation about 02:00 (second time), when the vegetal/ventral lip has "closed" and most involution has ceased (as in most other species, the end of gastrulation overlaps the begining of neurulation). Shows the initial formation of the posterior neural plate.

epi 03b 20fps


Mostly as above for epi 03b, but shows the lateral to medial "sweep" of tissue as the neural folds form..

epi 05b 20fps


Same embryo as in epi 08a. A somewhat later view of neural plate morphogenesis.

epi 08b 20 fps


A bit of later neural morphogenesis, showing posterior closure, at least in the right embryo.

H.s. NP 1ab 20fps


Early cleavage through gastrulation. You can see epiboly, probably just before or as gastrulation starts, and then (if you squint), you can see mesendoderm migration (much sloppier than in Xenopus), as gastrulation gets underway. Toward the end you can see the embryos swelling.

Cleavage 1abc 20 fps