Which is Eaton agent?

Ref: Ananthnarayan R. Paniker CKJ. Textbook of Microbiology. 8th Edition. Hyderabad: Universities Press: 2009. Pg. 389.Explanation:Mycoplasma pneumoniae causes primary atypical pneumoniaEaton (1944) was the first to isolate the causative agent of the disease in hamsters and cotton rats.He was able to transmit the infection later to chick embryos by amniotic inoculation.Because it was filterable, it was considered to be a virus (Eaton agent), but was subsequently shown to be a mycoplasma and named M pneumoniae.