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		Results Over a period of five days, the attrition rate for embryos in this experiment was as follows. In attempting to dejelly the embryos, 17 attempts out of 29 (58.6%) were successful. Six embryos were therefore lost while dejellying. While cutting grafts from the donor embryos, 12 attempts out of 20 (60.0%) were successful in procuring transplant tissue. Placing the graft tissue into the host embryos seemed less problematic, with ten out of twelve attempts successful (83.3%). Finally, of the ten grafts that were placed, four grafts survived until the next day, meaning that the embryo was alive with its graft still in place. Three survived to the second day of observation, two survived to the third day of observation, and one (just) survived to the fourth day of observation. Observations were then stopped. Below is the table of observations. Date (m/d/yr) Day Observations # Surviving grafts 3/2/04 1 All grafts look quite good; LF (Lauren Fety) has three, LT (Laura Twichell) has five, AC (Anisha Chandra) has two. There is also a control. Embryo donors are at Stage 15/16. Embryo hosts are at Stage 25. Ten 3/3/04 2 10:00 am. Out of the ten original grafts, five have lost their grafts (two LF, three LT) and five remain. Embryos are at about Stage 29. 5:10 pm. Neural cords are much more defined; have elongated. Embryos area at Stage 31. One graft is not intact (LT). AC 1 has a ragged edge around its graft; AC 2 has healed well. LF's graft looks nearly perfectly healed. Four grafts remain. Embryos are at approximately Stage 31. 10:30 pm. No change in embryos; however, AC 2 got gash in side when moved w/eyebrow hair. Attempted to patch wound. Embryos are visibly older, at about Stage 32-33. Four 3/4/04 3 1:30 pm. AC 2 has 'exploded', spilling contents over dish. Embryos were transferred to 50% HEPES this morning. AC 1, LT, and LF still appear to have grafts intact. 4:30 pm. Cleaned out remnants of dead embryos from dish; all three embryos with grafts intact move when touched (show reflex movement for first time). Are elongated with distinct tail buds and visible spinal chords. Seem to have reached Stage 35. Three 3/5/04 4 6 pm. AC 1 has also 'exploded', rejected the graft (floating freely in solution), and is dead. LT, LF embryos do not show much change (opportunity to observe today was limited to five minutes). Changed embryos from 50% to 20 % rearing solution. Two embryos remain. Stage 36. Two 3/6/04 5 10:30 am. LT embryo alive but graft has been rejected (floating in solution). Can see spinal column, tail, clearly. Moves when approached with eyebrow hair. Control (dejellied egg but did not operate) embryo has grown into a textbook specimen. Moves continually, has balancers, responds to light (difficult to photograph!). LF is alive, has balancers, but also has rejected its graft. LT embryo is alive with balancers, tail, and...what is presumably eye tissue in the middle of its back! It is not moving and appears to be in an unstable condition. (Perhaps it is affected by death of other embryo in dish overnight). Will probably not survive long. One