Sunday Dec 24-1911. Miami, Crossed again Biscayne Bay to Ocean Beach and Collected a number of small shells near the opening through the Peninsular. Found a heart within and King Conch, the latter from Nassau in the Bahamas. Biscayne bay is not at all of dark water as stated by Agassiz. On the peninsula side the water is as clear as the ocean but on the Florida side the water is somewhat darker but it is by no means bogy water. On the Florida side one notes not only barnacles and oysters on the pier, but on the ground one sees nearly a Fucus and often many dead hirabers indicating that considerable life is buried in the calcareous mud bottom. The mud on the Florida is a very small and is essentially quartz sand. The bottom of the bay so far as I can see it is calcareous ground. Then too the color of the water is dependent upon what grows on the bottom, When there are plants the water takes on a dark color and one can see those patches among the lighter colored waters where the bottom is white sand. As one goes across it is seen that the bay is very shallow and that many horseshoe crabs have come to