What is the difference between 这类 and 这种?
种类 (n): 'kind, sort, kind, species'



  种 as a noun means carries the meaning of 'seed'



种: things came from the same origin and divert slightly, but still belong to the same kind nonetheless. 


For example, knife and sword are both a kind(种) of cold weapon because 'created to be a cold weapon' is their origin; Football and basketball are both a kind of a ball sport because 'created to be a ball sport' is their origin. 


  类 as a verb carries the meaning of 'to classify'



类: things that's being classified into the same sort, type or kind based on similar origin, feature,  function or other qualities  


For example, knife and sword are both a kind/ class/ type(类) of cold weapon ; Horse and cow are both a kind of cattle; Football and basketball are both a kind of ball sport. (we classify them based on their similarity)