The rete ovarii is a structure formed from the primary

sex cord In embryogenesis, the sex cords (primitive sex cords, primitive seminiferous cords, or gonadal cords) are structures that develop from the genital ridges that further differentiate based on an embryo's sex. After sexual differentiation, at day 49, ...

s in females. It is the counterpart of the

rete testis The rete testis ( ) is an anastomosing network of delicate tubules located in the hilum of the testicle ( mediastinum testis) that carries sperm from the seminiferous tubules to the efferent ducts. It is the counterpart of the rete ovarii in f ...

in males.Definition: rete ovarii from Online Medical Dictionary
/ref> It is a narrow hilus, at which

nerves A nerve is an enclosed, cable-like bundle of nerve fibers (called axons) in the peripheral nervous system. A nerve transmits electrical impulses. It is the basic unit of the peripheral nervous system. A nerve provides a common pathway for the e ...

and

vessels Vessel(s) or The Vessel may refer to: Biology *Blood vessel, a part of the circulatory system and function to transport blood throughout the body *Lymphatic vessel, a thin walled, valved structure that carries lymph *Vessel element, a narrow wat ...

enter the

ovary The ovary is an organ in the female reproductive system that produces an ovum. When released, this travels down the fallopian tube into the uterus, where it may become fertilized by a sperm. There is an ovary () found on each side of the bod ...

. In the

medulla Medulla or Medullary may refer to: Science * Medulla oblongata, a part of the brain stem * Renal medulla, a part of the kidney * Adrenal medulla, a part of the adrenal gland * Medulla of ovary, a stroma in the center of the ovary * Medulla of ...

of the

mammalian Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...

ovary near the hilus are small masses of blind

tubules In biology, a tubule is a general term referring to small tube or similar type of structure. Specifically, tubule can refer to: * a small tube or fistular structure * a minute tube lined with glandular epithelium * any hollow cylindrical body stru ...

or solid cords—the rete ovarii—which are

homologous Homology may refer to: Sciences Biology *Homology (biology), any characteristic of biological organisms that is derived from a common ancestor *Sequence homology, biological homology between DNA, RNA, or protein sequences * Homologous chrom ...

(i.e., of the same embryonic origin) with the rete testis in the male. The microscopic right ovary of

birds Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweig ...

usually consists only of medullary tissue.

References

Embryology of urogenital system {{developmental-biology-stub