In the study of the life histories of lower organisms, development of ways and means of rearing them successfully in the laboratory is of great importance. Experimental work on the embryology of invertebrates is a tedious and painstaking work. This paper is primarily a description of some methods tried in culturing an echinoid in the laboratory through artificial fertilization. It is hoped that it may contribute some knowledge to the embryology of echinoids. This work was done at the U.P. Marine Biological Station in Puerto Galera, Mindoro, during the summer session of 1948. With limited facilities, the writer performed the experiments on the embryology of an echinoderm, using Diademcu setosum (Leske), a black, long- spined and poisonous sea urchin.