A ground section was prepared from a lower right M3 attributed to Gigantopithecus blacki as close as possible to axial plane of the mesial cusps. Daily cross striations were imaged, measured and counted in each cusp using polarised light microscopy. Long-period striae of Retzius were counted in the lateral enamel and their periodicity determined from counts and measurements of daily cross striations between adjacent striae. Cross striation spacings in the cusps were between 3.8 microm at the enamel dentine junction and 6 microm close to the enamel surface. Cuspal enamel formation times were long (800 days in the protoconid and 620 days in the metaconid). Linear enamel thickness was as much as 3.75 mm in the protoconid. There were 63 and 61 long-period striae of Retzius in the mesial aspects of the lateral enamel and the periodicity was 11 days. Lateral enamel formation took 1493 and 1291 days and when summed with cuspal enamel formation times totalled 4 years in the protoconid and 3.5 in the metaconid. Relative enamel thickness was 23, calculated through the mesial cusps. This falls short of that in the so-called 'thick hyper-thick' enamel described in 'robust' australopithecines to which Gigantopithecus blacki has previously been compared in both its dental and mandibular morphology. With respect to enamel thickness, therefore, Gigantopithecus blacki falls squarely among an increasingly large number of Miocene hominoids that can all be described as having 'thick enamel'.

中文翻译：

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黑色长臂猿第三个恒磨牙的牙釉质厚度和发育。

从右下角M3制备了一个地面部分，该区域应归因于黑长臂猿，尽可能靠近中尖瓣的轴向平面。使用偏振光显微镜对每个尖点处的每日交叉条纹进行成像，测量和计数。在侧釉质中计数Retzius的长周期纹，并根据相邻纹之间的每日交叉纹的计数和测量确定其周期性。牙釉质牙本质交界处牙尖的交叉条纹间距在3.8微米与靠近牙釉质表面的6微米之间。s骨牙釉质的形成时间很长（原分生孢子中的时间为800天，后分生孢子中的时间为620天）。在原始分生孢子中，线性釉质厚度高达3.75mm。在侧釉质的内侧部分，Retzius有63和61个长周期纹，周期为11天。牙釉质的外侧形成需要1493天和1291天，加上牙髓的形成时间，在原分生孢子中总计为4年，在后分生孢子中为3.5年。牙釉质的相对厚度为23，通过牙尖计算。这与以前在牙齿和下颌形态上已经被比较过的“健壮的”澳大利亚古猿中描述的所谓的“厚实的超厚”搪瓷中的釉质相去甚远。因此，就釉质的厚度而言，黑色长臂猿（Gigantopiththecus blacki）正处于越来越多的中新世类人动物中，这些中新世人类人都可以被描述为具有“厚釉质”。通过内侧尖瓣计算。这与以前在牙齿和下颌形态上已经被比较过的“健壮的”澳大利亚古猿中描述的所谓的“厚实的超厚”搪瓷中的釉质相去甚远。因此，就釉质的厚度而言，黑色长臂猿（Gigantopiththecus blacki）正处于越来越多的中新世类人动物中，这些中新世人类人都可以被描述为具有“厚釉质”。通过内侧尖瓣计算。这与以前在牙齿和下颌形态上已经被比较过的“健壮的”澳大利亚古猿中描述的所谓的“厚实的超厚”搪瓷中的釉质相去甚远。因此，就釉质的厚度而言，黑色长臂猿（Gigantopiththecus blacki）正处于越来越多的中新世类人动物中，这些中新世人类人都可以被描述为具有“厚釉质”。