- 04 Jun 2017
Pila is a unisexual animal. Males and females are separate. Male is smaller than female. Male will show penis at the end of vas deferens.
Male Reproductive System
It shows testis, vas deferens and penis.
1. Testis: Only one testis is present. It is present in the visceral mass.
2. Vas deferens: From testis a number of vas efferentja will arise. They unite to form vas deferens. This is divisible into 3 parts.
- Proximal tubular part: It is thin tube, it is narrow.
- Middle curved part: It is curved. It is bulged. It will store sperms.
- Distal glandular part: The last part is glandular. It will open on the genital papilla.
3. Penis: In front the anus from the edge of mantle a curved penis will arise ii is called Penis. It shows a groove. Through this groove sperms will travel
Hypo branchial gland: Near the base of penis a big hypo-branchial gland is present. Its functions are not clearly known.
Sperms: In pila two types of sperms are formed.
- Enpyrene type: They are thin. They show head, middle piece and tail. They are 25 microns in length. They can swim. The tail has a cilium. These sperms can fertilize the ovum.
- Oligopyrene sperms: These are sickle shaped. They show 4 to 5 cilia. They are 32.5 microns in length. Specific head is not seen. They cannot move They can never fertilise.
Female Reproductive System
In the female reproductive system ovary, oviduct, seminal receptacle and uterus are present.
1. Ovary: It is present above the hepato-pancreas. It is branched. It is light orange coloured. When it is mature it becomes black. It gives oviduct.
2. Oviduct: It is a narrow duct. It opens into seminal receptacle.
3. Seminal Receptacle: It is bean shaped bulged organ. It will receive the sperr s from male during copulation.
4. Utirus: It is a big yellow coloured sac. Seminal receptacle will open into it. At it a 2X vagina is present. It opens out through female genital aperture near the anus.
In the rainy season copulation will take place between male and female >ilas. Male and female will attach in opposite directions. Male will inject sperms through penis into the seminal receptacle of the female.
In the uterus fertilization is carried on. They are liberated on moist places by female. They hatch and give small organism which resemble the adult pila.