4G Robert E. Coker. 



PAirr 11. THE SCUTES OF THALASSOCIIELYS 



CARETTA (L.). 



1. Inteoduction, 



Material. 



Only embryos and young were observed and these were obtained 

 from eggs laid on the ocean beach near Beaufort. In studying the 

 abnormalities it is important to know the conditions under which 

 the embryos developed. The laying ground is inconveniently dis- 

 tant from the laboratory and the nests could be visited only by a 

 sail and a walk on the beach that consumed the greater part of a 

 day. The main object at the time was the collection of embryo- 

 logical material, and, as it was important to have the eggs conve- 

 niently accessible, it was necessary to remove them to artificial nests 

 on the island on which the laboratory is situated. Another condi- 

 tion making it advisable to transplant the eggs was the difficulty 

 of protecting the natural nests from depredation. Turtle eggs have 

 a local value as food and are eagerly sought by fishermen.. It was 

 observed too that hogs root up the nests and destroy the eggs. 



One nest was left undisturbed. A wire screen, placed over it 

 and well under the sand, served to prevent the escape of the young 

 turtles and to protect the nest from hogs. Traces of the nest were 

 obscured as far as possible to prevent molestation by fishermen. The 

 eggs hatched successfully (see Table VIII). 



Most of the eggs were removed from the nests within two days 

 after they were laid, usually on the following morning, and transr 

 ferred in a bucket or box, in which they were covered with moist 

 sand and seaweed. Usually care was taken to keep the eggs right side 

 up. The eggs were then replanted either in artificial nests on the 

 ground or in a sand-box or "incubator." The artificial nests in the 

 ground were not successful. The soil, though chiefly sand, was of a 

 different composition, and a higher temperature obtained than at the 

 same depth on the beach. Other environmental conditions seemed 

 unfavorable, and, in consequence, but a small proportion developed to 

 a late stage. Unfortunately, the first observations indicated that nests 

 in the ground would be more satisfactory than nests in an incul)ator, 



