1. In max, create 2 geo-spheres. Scale one in the x-axis and the other in the z-axis.
2. Convert both of them into "editable poly" objects.
3. Apply a mest smooth modifier with irritations value:2 & smoothness:1
4. Go in editable poly stack, activate edges & select all the edges of the geo-sphere
5. Extrude them: -height at a negative value , base width at a positive value.
(Just play between these 2 values tii you get the results you want)
*On forgot, if you prefer sculpting rather than scaling, use the paint-deformer tool in max available in the edit poly stack.
Here is just a rough result created in 3 mins
I know its not the same. I just roughly created it.
You need to later add a displacement map for the ballon effect