The red sea urchin (Mesocentrotus franciscanus) is found in the Pacific Ocean from Alaska ti Baja California. It lives in shallow waters from the low-tide line to greater than 330 feet deep, and is typically found on rocky shores sheltered from extreme wave action. A sea urchin’s spherical body is completely covered by sharp spines that can grow up to 3.1 inches. These spines grow on a hard shell called the “test”, which encloses the animal. It can vary in color from red to dark burgundy. A sea urchin has no visible eyes or legs. It has a mouth located on its underside, which is surrounded by five teeth. The sketch is direct to watercolor without ink. Holbein and Daniel Smith watercolors in a Stillman and Birn sketchbook.