These drawings are the work of Dr. Frank Netter, of course, for those of you who saw his work in medical school -- over and over. This is from the CIBA collection of his work. Do not copy these figures, please.
A reader who admired Netter's illustrations offered to remove the lines Netter had drawn, naming the substructures. The result is an image that I think Dr. Netter himself would be very pleased to know was being used in this way. Thank you very much, Steve.