470 ANNUAL EEPOBT SMITHSONIAN INSTITUTION, 1917. 



sea bean and the moon vine and the goat-foot morning-glory, while 

 within the Avail several species of palms and a grove of buttonwood, 

 Cordia trees and ornamental shrubs furnish a favorite retreat to the 

 many lesser migratory birds. Bird Key has an almost dead fringe 

 of bay cedars and a few coconut palms near the house and a scattered, 

 scant growth of cactus and grass, as well as a few ornamental shrubs 

 near the buildings. The largest of the keys is Loggerhead Key, the 

 center of which is occupied by Loggerhead Light, a first-class, re- 

 volving, flashing beacon that projects a beam for more than 18 

 miles, and the buildings necessary to quarter the attendants. On the 

 west central portion is a boat shed and pier, while the east central 

 portion is provided with another pier and landing stage. On the 

 northern end of the island the buildings of the Marine Biological 

 Laboratory of the Carnegie Institution are nestled in a growth of 

 palms, maritime pines, and flowering shrubs, fringed on the sea side 

 by bay cedars, Tournefortias, and Bermuda grass. Excepting the 

 introduced palms, figs and other ornamental plants about the labora- 

 tory and the light, the most conspicuous vegetal features of the island 

 are the bay cedars, which practically girdle, and in many places com- 

 pletely cross it. These attain a height of more than 10 feet. This 

 covering of bay cedars is irregularly interrupted by grassy meadows, 

 where the short crab grass and spear grass vie with the flat-leaved 

 cactus for supremacy. The scattered huge agaves south of the light- 

 house usually rear some flowering stalks, which furnish a favorite 

 resting place for the hawks during the migratory season. A Cordia 

 grove occupies the east shore line a little north of the light, and 

 here and there groups of ashy leaved Tournefortias lend a funereal 

 aspect to the beach. In places, dense growths of Bermuda grass oc- 

 cur immediately above the reach of the storm tide and wave their 

 abundant, shimmering heads of seeds in a most pleasing manner. In 

 other regions, similar reaches are covered by a fuzzy, brown-topped 

 sedge, while still other places are measured by the long trailing vines 

 of the goat-foot morning-glory (Ipomaea pes-caprae) , the moon vine 

 Colony ction tuba), and the sea bean (Canavali lineata). 



The most interesting island of the group is Bird Key, for of the 

 32,810 birds listed for the group in last summer's census, 31,200 center 

 about this key. In the list given below the numbers in italic refer 

 to Bird Key inhabitants. 



A numerical list of the summer lirds of the Tortugas. 

 (Based upon observations made between July 1&-31, 1917.) 



Laughing gull 2 



Royal tern 24 



, ( adult 200 



Roseate tern .. estimated < 0/vr . 



| young 300 



