Does such a reference book exist?

There are many books available for identifiying the exact species of an organism. The way they are set up is simple: navigate to a broad quality (i.e. Coniferous) and then gradually narrow it down by going to the page(s) that correspond to whichever of the listed discriptions that follow apply to the organism (i.e. Has short needles).

I get the feeling that one would need the entire cannabis plant available for inspection to narrow it down to even a semi-accurate conclusion, but I'm still curious nevertheless. Anyone ever seen or heard of such text?

 

*brain explosion*

 

^ditto

 

I'll assume you talking about weed...

http://en.wikipedia.org/wiki/Cannabis
http://www.erowid.org/plants/cannabis/cannabis.shtml

and if you want a physical text:
http://www.plantsciencenetbase.com/ejournals/books/book_summary/summary.asp?id=2406

 

Ahhh mycology. Buy a mycology textbook.. or google it.

 

Mycology? you mean the study of fungi?

 

yeah I meant taxonomy