Decker J D
Science. 1967 Aug 25;157(3791):952-4. doi: 10.1126/science.157.3791.952-a.
Periodic motility of turtle embryos was observed during their incubation periods (60 +/- 5 days). Cyclic activity was first observed between days 10 to 14; it increased to a peak level of 50 percent of the standard observation period on day 30 +/- 5, then declined to low levels until hatching activities were initiated. During the first third of the incubation period, motility of the turtles closely resembled that previously described for chick embryos at similar stages of development.
在海龟胚胎的孵化期（60±5天）观察到周期性运动。在第10至14天首次观察到周期性活动；在第30±5天增加到标准观察期的50%的峰值水平，然后下降到低水平，直到开始孵化活动。在孵化期的前三分之一时间里，海龟的运动与之前描述的处于相似发育阶段的鸡胚胎的运动非常相似。
