四爪陆龟骨骼系统的解剖

THE ANATOMY OF THE SKELETAL OF Testudo Horsfieldi GRAY

对四爪陆龟Testudo horsfieldi Gray骨骼系统进行了解剖观察,其背甲椭圆形,背面拱起,椎板具5种形状,肋板内、外缘的长度呈内长外短,外长内短交替,腹甲上板明显增厚突出,内板内表面大致呈三角形,外表面则略圆,脊柱公式为:C_9D_(10)S_2C_(y18(21))=39(42),颈椎变化较多,具前凹、后凹、双凸、双凹4种类型的椎体,寰椎环状,椎弓发达,枢椎小,无椎弓,第7颈椎的椎体后端和第9颈椎的椎体前端分化成两个关节凸面,同时第8颈椎椎体的前后端均分化成两个关节凹面,躯椎10枚,第1躯椎较为特化,单头肋骨10对,第9,10对的肋骨的远端膨大,并与荐肋愈合,扩展至第8对肋骨板上,构成荐骼关节的一部分,第1,2尾椎的尾肋也参与荐髂关节的构成,头骨小,颅全长为颅宽的1.51倍,硬腭达眼眶的后半,无颞窝,但具有相当于颞窝的颓区凹陷,鳞骨小,枕骨嵴短,舌骨前角发达,前肢骨比后肢内粗壮,腕堂骨、跗蹠骨和指趾骨均有愈合和减少。

Because of the particularities of its skeletal the skeletal muscular system has adaptive ones.The trunk musculature shrinks and disappears. meanwhile many new muscules which exist only in chelonia come into existenec such as m. testo-coracoideus, m. testo-scapula coracoideus, m. (esto-superctrvico-cutaneus. m. testo-cervicalis, m. testo-iliacus, m. testo-caudalis etc. Some former muscules also attach to the carapace, plastron in order to withdraw much quikly the head,neck, fore-hind-limbs and tail into the shell when it is disturbed. M. masseter and m. temporalis are strong. Two pairs of m. coraco-hyoicieus, a pair of m. pubo-caudalis instead of m. ilio-caudalis and a pair of long and thin muscules originating from the vertebral colum and attaching to the ventral of cloaca are obserred. The appendicular muscles and tail muscules are very strong.