t h e  h a n d s p t 2
dhayana mudra
Sitting in meditation is a very important part of Buddhism.
When you sit down the hands tend to rest in the lap quite naturally in this position.
This is a gesture of the concentrated mind in meditation.
vitarka mudra
The Buddha's teachings are often presented in list form and with this gesture one could imagine Gotama counting off the 'Four Noble Truths' -- one to each finger. This mudra is similar to the Dhammacakka mudra.
It is a gesture of reasoning -- of offering teachings.