On the Structure of the Ovary and the Ovarian Ovum of Loris lydekkerianus, Cabr

Abstract

There is a definite polarity in the ovarian ova as regards the distribution of the fat-bodies in the younger as well as the fully grown examples. It has not been possible to distinguish two types of ova based on the size or distribution of these deutoplasmic inclusions. The deutoplasmic pole is occupied by fat-bodies of uniformly small size, while the periphery and the plastic or nuclear pole are distinguished by the occurrence of small and large varieties of fat-spherules. Nuclear emission takes place very early in the growth of the ovum and initiates the formation of fat-bodies, and in doing so the nucleolus itself increases in size, while in the final stages of its catalytic activities it diminishes before final expulsion into the follicle cells where it is absorbed. The formation of yolk-disks is attributable to the agency of micrometachondria whose general distribution accords with the appearance of yolk and with which they are in intimate relation. Having given rise to the yolk-disks, they disappear from the fully grown ova. The Golgi bodies also initiate the formation of yolk which appears in the archoplasm, and in this process the Golgi rods are noticed to undergo appreciable diminution in size. Later in the development of the ovum the Golgi rods form a close cap on the nuclear membrane, and those which have not participated in the formation of yolk lie scattered in the general cytoplasm. Deep imaginations and their secondary ramifications occur in the ovary throughout the life of the lemur, and fresh ova arise from the germinal layers of these invaginations as well as the interstitial cells. The nuclear changes involved in the production of fresh ova are in accord with the observations already published by the other authors who have studied these changes in the rabbit, and the only point worth recording is that the diplotenic stage is less clearly marked and the dictyate stage is speeded up in the lemur.