how did the above mentioned garden become a part of the university?
After 1917 when the University took over the garden from the Swedish Linnaean Society.
Linnaean Garden
 It was bought by the Swedish Linnaean Society in 1917 and restored according to the detailed description in the "Hortus Upsaliensis". 
what is the red mushroom with white dots Amanita muscaria how did it get its name? The name in many European languages is thought to derive from its use as an insecticide when sprinkled in milk. Its scientific name was, however, given by Linnaeus and Lamarck. is it considered to be poisonous? Yes, it can be poisonous if ingested. how is it treated to make it suitable for culinary purposes? By parboiling it. where did the first taxonomist you named hail from? From the village of Råshult in Småland, Sweden. did he author any books or manuscripts? Yes, he wrote a thesis ,'on plant sexual reproduction' along with many more manuscripts. He also wrote a book on the plants grown n the Uppsala Botanical Garden. and where is this botanical garden located? Uppsala University in Sweden. how old is this university? Almost 544 years as it was founded in 1477.
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Linnaean Garden [SEP] Introduction
After the gardens of Uppsala Castle had been donated to the university by King Gustav III to serve as a new botanical garden, the old one was left to decay. It was bought by the Swedish Linnaean Society in 1917 and restored according to the detailed description in the "Hortus Upsaliensis". The garden was later taken over by the university, while the Linnaean Museum in the house in which Linnaeus had his home is still run by the Society. It is now one of two satellite gardens of the larger University of Uppsala Botanic Garden near Uppsala Castle. The second satellite is Linnaeus Hammarby, the former summer home of Linnaeus and his family.