The observations recorded in the following pages are the 

 outcome of a vacation-journey undertaken in the summer of 

 1888 in company with a class of students frord the Academy 

 of Natural Sciences of Philadelphia. My main object in visit- 

 ing the islands was to satisfy my mind on certain points con- 

 nected with the structure and physiognomy of coral reefs, to 

 the study of which the Bermudas offer special advantages. I 

 contemplated but little work in zoology, and that which was 

 accomplished may be considered supplemental to the plan of 

 work originally laid out. It was not until my return to Phil- 

 adelphia that I was made aware of tlie extent of the zoological 

 material collected by us, and how little systematic study of the 

 fauna of the region had been made prior to our visit. Some 

 of our material still awaits examination ; for the elaboration 

 of that portion which is delineated in the present volume I 

 am largely indebted to the labors of a number of specialists 

 who have kindly volunteered their assistance. In this connection 

 I desire to acknowledge my indebtedness to Prof J. Playfair 



