Fiqh (فقه) is Islamic jurisprudence. Fiqh is often described as the human understanding of the sharia, that is human understanding of the divine Islamic law as revealed in the Quran and the teachings and practices of the Prophet Muhammad and his Ahl al-Bayt.
Ahlul Bayt (AS) taught their sincere students and encouraged them to write in may important subjects including Fiqh. Ali Ibn Ja'far wrote a book in this subject and many other students of Ahlul Bayt (AS) wrote Fiqh books.
The chain of transmitters from Imam Ja'far as-Sadiq (AS) are mentioned
in books of E'lm Al-Rijaal like Rijaal Al-Kishshi and many similar books of
narrators like :
1. Wasael Al-Shia by Al-Hurr Al-Amili
2. Kitab Al-Najaashi
3. Rijal Al-Toosi
4. Al-Fihrist by Al-Toosi
5. Fihrist Muntajab al-Deen al Qummi
6. Ma'alim al-Ulama by Ibn Shahr Aashoob
7. Al-Tahreer al-Taawoosi
8. Rijal Ibn Abi Dawood
9. Jami' Al-Ruwaat by Al-Ardabili
10. Tanqeeh Al-Maqal by Al-Mamaqaani
11. Rijal Al-Kalbasi by abi Al-Huda Al-Kalbasi
12. Thiqaat Ar-Rijal by Hibat Al-Deen Al-Shahrastani
13. Mo'jam Rijal Al-Hadeeth by Al-Sayyed Al-Khoei
14. Khaatimat Kitab Wasael Al-Shia by Al-Hurr Al-Amili
15. Al-Mausoo'ah Al-Rijaaliyah Al-Muyassarah by Sheikh Al-Turabi and
From all animals of water we are allowed to eat :
1. Fish which has or had scales on it. Fish which has no scales at all are not allowed to eat.
2. Shrimps or prawns.
All other water animals e.g. crab, oyster, shells, lobster, ink fish etc is not allowed to eat.
The reply depends on what you mean by adoption. If you mean looking after and bringing up a child, then it is great deed of reward. The Hadeeth says: Best of the homes is a home where an orphan lives with honor. Also it is narrated from the Prophet Muhammad (SAWA): I and orphan sponsor are in the Paradise together.
But if you mean to look after the child and deprive him from the name of his real father , mother and original family, then it is unlawful in Islam to deprive the child from the name of his father, mother and original family.
Allah says in Quran (Call them by their fathers' name)(ادعوهم لابائهم)Al-Ahzaab,5.
Also it is not allowed to deprive the child from his real mother (إن أمهاتهم إلا اللائي ولدنهم )(Their mothers really are who gave birth to them) Al-Mujadalah ;2.
Claiming the adopted child as a real son or daughter is forbidden in Quran (وما جعل أدعياءكم أبناءكم ذلك قولكم بأفواهكم ) (Allah did not make your sponsored/ adopted/ fostered children as your children, that is what you say in your mouths).
So, it is very good to adopt a needy child with keeping his father's, mother's and family name with him always.
One has to assume that if the possessors of these books chose not to share them, then it is not necessary for us to know the contents. Mushaf Fatimah and al-Jafr, according to hadith, contain more than fiqh and shari'ah; for instance, according to hadith, they contain detailed future prophecies, and perhaps this information would not be beneficial for us. According to hadith, Mushaf Fatimah was narrated to her as a form of consolation due to her grief for her father, so from that angle, there may have been a personal purpose.
There are a number of sacred items mentioned in hadith as being passed on from the prophets to the Imams as a sign of spiritual authority and these can be looked at in this light.
There is no indication that the Imams required these materials to learn, but that does not mean that there is any problem in their having them or consulting them. Perhaps it was reassuring to some people around them, who did not believe in the imamate, that they were referring to texts received from their forebears.
We live in an era where the value of things is measured very materially, especially in the era of the Internet, when it is assumed that anything worthwhile should be shared publicly. However, this brings up the question of, do things have value if people do not see them? (For instance, a tree in a forest.) Is it possible for something to have purpose if it is seen by only one or a handful of people? It is reasonable to argue that there is a spiritual value to the existence of these items; however, for them to have an existential value, it is not necessary that they be available to the majority of people.
As far as sea food is concerned, only that fish which has scales may be consumed. In addition, it must be alive when caught from the water. Crabs are not classified as fish and may not be consumed. There is some differences amongst certain ulama' regarding lobsters but the general consensus seems to be that it should not be consumed. See Ayatullah Seestani's Islamic Laws p. 489.