. Asiatic herpetological research. Reptiles -- Asia Periodicals; Amphibians -- Asia Periodicals. 2001 Asiatic Herpetological Research Vol. 9, p. 3 > o •B 7 9? o e a> o o <U o5 3-. J I L J I I I l_L 10 11 12 1 2 3 4 5 6 7 8 9 month Figure 1. The seasonal change of Mature coefficient of ovary (1991-1993) Eggs. The mean number of eggs spawned in each batch is about 218. The egg of R. boulengeri is big with a mean diameter of mm, enveloped by 3 layers of gum membrane (The diameter of egg includ- ing membrane is mm). The outer layer is the thickest, the inner layer the thinnest.
. Asiatic herpetological research. Reptiles -- Asia Periodicals; Amphibians -- Asia Periodicals. 2001 Asiatic Herpetological Research Vol. 9, p. 3 > o •B 7 9? o e a> o o <U o5 3-. J I L J I I I l_L 10 11 12 1 2 3 4 5 6 7 8 9 month Figure 1. The seasonal change of Mature coefficient of ovary (1991-1993) Eggs. The mean number of eggs spawned in each batch is about 218. The egg of R. boulengeri is big with a mean diameter of mm, enveloped by 3 layers of gum membrane (The diameter of egg includ- ing membrane is mm). The outer layer is the thickest, the inner layer the thinnest. The outer layer is very sticky, so that many eggs connect together to form a long cluster, the end of egg cluster is stuck on the wall or to ratty plants under water. Development of genital glands Development of ovary. The development of ovary can be divided into 6 stages. Stage 1. Multiplication period of ovogonium: The body weights (BW) of young frogs are g and the body lengths (BL) are mm. The ovogo- nium cells, aggregating densely with the ability of division, have not been surrounded by follicle cells. Stage 2. Growth of ovocyte (oocyte): When the BW of young frog are g and BL are mm, ovogonium cells develop into ovocyte cells. The ovocyte clusters are divided by connective tissue of the ovary and surrounded by follicle cells. Stage 3. Transition growth of ovocyte: When BW of young frog are g and BL are mm, the volume of ovocyte cells increases. The follicle cells increase from 1 to 2 layers and the zona pellu- cida becomes clear. Early stage 4. Formation of yolk in ovocyte: When young frogs weigh g and their BL are mm, oocytes begin rapid growth and particles of yolk begin to form. Late stage 4. Ovocyte cells filled with yolk: When frogs have BW of g and BL of mm, the ovum cells are fully filled with yolk and the nuclei are isolated in the middle of the cells. The two l
Size: 1599px × 1563px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcollectionbiodiversity, bookcontributorharvarduniversitymus
