THE SPINY LOBSTER OF SOUTHERN FLORIDA. 



EXPERIMENTS IN HATCHING. 



309 



Preliminary experiments were made by the junior author in 1917, which showed 

 that the eggs would hatch while attached to females placed in floating boxes. The 

 young, however, could not be reared in such apparatus and died within a day or two after 

 hatching. 



Another attempt was made to hatch the larvae in 1918. The eggs were stripped from 

 a number of females and placed in MacDonald hatching jars, which were supplied with 



Fig. 273 — Newly hatched larva of spiny lobster, Panulirus argus, hatched nt Key West (Fla.) Biological Station. June. 1918. 



X 33'/i. approximately 



running salt water. This method proved to be more convenient than floating boxes for 

 observation, but as a practical method it can not be recommended, since a very small 

 per cent of the eggs hatched normally. It was found that the eggs hatch much better 

 when left on the pleopods of the female. Newly laid eggs were observed to be slightly 

 heavier than water, but as the embryo develops the specific gravity of the eggs decreases, 

 and when the eye of the embryo is visible the eggs are more buoyant. The newly laid 



