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Skull · The skull of Rabbit consists of two regions:      (A) Posterior Cranial region &      (B) Anterior Facial region 1. Cranial Region · The cranial part is shorter than the facial part. · Cranium, which forms the braincase, encloses the brain. · Cranium is divided into three segments which are Occipital segments, Parietal segments and Frontal segments. A. Occipital segment: · This segment includes four bones that surround the foramen magnum. · They are supra-occipital lies just above the foramen (1), exoccipitals (2) located at both of the lateral sides of foramen and basioccipital  (1) that lies on the floor of the foramen. · The skull of a rabbit is dicondylic because it has two occipital condyles. B. Parietal segments: · This segment consists of five bones. · They are parietal (2) in the roof, alisphenoids (2) in the lateral sides, and basisphenoid (1) on the floor. · Basisphenoid h...

The Nervous system of a rabbit can be divided into: 1. Central Nervous System (CNS) – It includes the Brain and spinal cord. 2. Peripheral nervous System (PNS) – Spinal and Cranial nerves 3. Autonomic Nervous System (ANS) – It includes Parasympathetic and Sympathetic nervous systems. ·  Nervous system is derived from ectoderm: except 2M : Microglia and meninges which are derived from mesoderm. A. CNS (Central Nervous System) 1. BRAIN ·  Brain is ectodermal in origin. ·  The brain is protected in the cranium or brain box and covered by Meninges. ·  Meninges are the coverings of the brain which consists of 3 layers. i) Dura mater: It is the toughest thick outermost layer that is attached to the cranium. ii) Arachnoid mater:  It is the middle, delicate, thin and vascular layer. iii) Pia mater: I t is the innermost or immediate covering of the brain & spinal cord. ·  It is a thin, soft and vascular layer. · ...

· In rabbits, the sexes are separate and sexual dimorphism is well marked. Male Reproductive System · The male reproductive organs include a pair of testes, a pair of the epididymis, a pair of vasa deferentia, urethra, penis and some accessory glands. A. Testes ·  The paired testes are small, ovoid bodies of light pink colour. · Each testis lies in scrotum which is located outside the abdominal cavity, ventrally in the pubic region. So-called  extra-abdominal testis. ·  In the foetus and newly born rabbit, the testes lie within the abdominal cavity near the kidneys where they were developed. But at puberty, they descend through inguinal canals into scrotal sacs. ·  The outer protective covering of testis is called tunica albuginea, formed by white fibrous connective tissue, which projects the testis. ·  In most species of mammals, the testes remain within scrotal sacs throughout life. · But in rabbits, rats and other rodents, they are migratory. Male reprodu...