Here are the top 10 Layer 2 coins by market capitalization, with numbering:
1. _Polygon (MATIC)_: $7.33 billion
2. _Arbitrum (ARB)_: $5.63 billion
3. _Optimism (OP)_: $4.34 billion
4. _Immutable X (IMX)_: $3.51 billion
5. _Mantle (MNT)_: $3.45 billion
6. _Loopring (LRC)_: $2.84 billion
7. _SKALE (SKL)_: $2.44 billion
8. _Metis (METIS)_: $2.34 billion
9. _Boba Network (BOBA)_: $2.23 billion
10. _Nitro (NITRO)_: $1.83 billion
Please note that the market capitalization of cryptocurrencies can fluctuate rapidly and may be different at the time of your inquiry.