Range of IP Address from 188.8.131.52 to 184.108.40.206 are
Class D addresses are 32-bit network addresses, meaning that all the values within the range of 220.127.116.11 – 18.104.22.168 are used to uniquely identify multicastgroups. There are no host addresses within the Class D address space, since all the hosts within a group share the group's IP address for receiver purposes
Octet 224 corresponds to 1110 which corresponds to Class D which is used for Multicast netwroking.
Bonus: Octet 1111 corresponds to Class E which is reserved for experimental purposes.