By using the bifurcation theory of planar dynamical systems and the method of detection functions , this paper gives a configuration of limit cycles forming compound eyes . with the help of numerical analysis ( using maple ) , it is shown that there exist parameter groups such that a polynomial vector field of degree 7 has at least 49 limit cycles with z8 - symmetry 然后，利用平面动力系统的分支理论以及判定函数法，考虑z _ 8 -等变的扰动hamilton向量场，在计算机数学软件( maple )的帮助下，我们得到结论： 8次平面向量场至少有49个极限环，形成具有z _ 8 -对称性的极限环分布。
We observed the surface structure and inner structure of the compound eyes . and we also studied the change process of the ultrastructure of the compound eyes in different light adaptation . comparative studies on the structure differences of photoreceptor between portunus tritubereulatus and metapenaeusensis were also done 运用电子显微镜技术观察了三疣梭子蟹( portunustritubereulatus )的光感受器的超微结构，对三疣梭子蟹复眼的外部形态、大小、内部超微结构，以及在不同光适应条件下的变化过程进行了研究；并且与刀额新对虾( metapenaeusensis )光感受器的超微结构进行了比较。
The results under scanning electron microscope were that the compound eye of miers is semi - globular . the surface area of the compound eyes is about 25 . 12mm2 . the ommatidia that form the compound eye are hexagon . on the back of the compound eye there is a thumb - shaped area where have no ommatidia 扫描电镜观察显示三疣梭子蟹的复眼外形为半球形，复眼表面积约为25 . 12mm ~ 2 ，背面有一拇指状的无眼区，组成复眼的小眼为长六边形；刀额新对虾的复眼外形为球形，背面无拇指状的无眼区，组成复眼的小眼为四边形。
We used four different wavelength light including red light ( 750nm ) , yellow light ( 580nm ) , green light ( 560nm ) , blue light ( 400nm ) to stimulate four different groups compound eyes . then the ultrastructures of the compound eyes of each group were observed under electron microscope . the results showed the fine structure of the photoreceptor , the diameter of rhabdom , the dimension of perirhabdom vacuole , the number of pinocytotic vesicle below the microsvilli , the location of pigment granules , the emergence of lamellar bodies and lysosomes in cytoplasm , were different in different light adaptation 二、不同光照条件下复眼超微结构的变化三疣梭子蟹经过12h暗适应后，在不同波长的红光( 750nm ) ，黄光( 580nm ) ，绿光( 560nm ) ，蓝光( 400nm )照射下，其光感受器的小网膜细胞和感杆束的形态和超微结构呈现较大的区别，感杆束的形态、细胞内的胞器随不同波长光的适应而发生变化，在红光下感杆束直径最大，微绒毛排列整齐，在蓝光下感杆束直径最小，微绒毛最凌乱。
