Is this cactus normal?

[PAHCace]

Hello

My cactus has unusual spherical growths at its base, and I am not sure whether this is typical of it or not.

Also the top is a slight different colour than the rest, more of a light brown rather than green.

Is this normal? Do you have any tips of how to improve its health?

Thank you

[teo]

Looks like a Mammillaria elongata. The pups at the base are normal (consider them as children) - the brown at the top might indicate an attack by red spider mites - try to look with a magnifying glass for tiny red specks. If so they should be killed - see: http://www.cactiguide.com/cactipests/#spidermite" onclick="window.open(this.href);return false;