2 q8 PAPERS FROM TORTUGAS LABORATORY vol. xxxiv 



Halichoeres bivittatus and young Thalassoma bijasciatum always accompany it, 

 just as they follow feeding goatfishes, for the purpose of catching any animal 

 that may be driven out of the sand and escape the trunkfish. 



The coloration is changeable. It is noticeably paler over sand, and more oli- 

 vaceous among gorgonians. The dark color of the body, with its white spots, is 

 continued from the margin of the orbit across the dorsal surface of the eye 

 beyond the outer margin of the iris, which is itself dark. W. H. L. 



There are no specimens in the collection. 



Atlantic coast of tropical America northward to North Carolina, sometimes 

 straying to Cape Cod. S. F. H. 



Lactophrys bicaudalis (Linnaeus) 



Nothing on this species was found among Dr. Longley's manuscripts, and no> 

 specimens in his collection. In his notebooks it seems to be mentioned only once, 

 the capture of a 75-mm. specimen being reported. 



Jordan and Thompson (Bull. U. S. Bur. Fish., vol. 24, 1904 (1905), p. 249) 

 reported it from Tortugas with the notation, "One seen. New to the United 

 States fauna." Gudger (Carnegie Inst. Wash. Pub. 391, 1929, p. 199) reported 

 2 specimens from Tortugas, with a description and photographic reproduction 

 of his smaller specimen, which was about 80 mm. long. 



The carapace behind the dorsal fin is fully closed, as it is in Lactophrys tri- 

 cornis, but unlike the latter it has no frontal spines (horns). 



West Indies to Florida. S. F. H. 



Lactophrys trigonus (Linnaeus) 



The young, 10 to 40 mm. in length, were seined commonly on the grass flats. 

 This species may be recognized at once by the single free plate on the dorsal 

 side of the caudal peduncle behind the dorsal fin. In young, 35 mm. in length,, 

 an angle in the ventral keel indicates the position of a future spine. 



In a specimen 160 mm. long it was noticed that the coloration was changeable, 

 and that elements in the pattern were homologous with parts of the dark bars 

 of Lactophrys tricornis. 



In an attempt to determine the efTect of the apparent motion of the bottom 

 below it on a swimming fish, specimens were tested in a glass-bottomed tank 

 beneath which an endless belt of figured cotton cloth was drawn. This fish 

 usually headed against the fictitious current and "stood" still. But if by chance it 

 turned, it could be raced down the length of the tank immediately. W. H. L. 



The collection contains 12 young, 20 to 55 mm. long. 



Atlantic coast of tropical America to Florida, sometimes straying northward 

 to Cape Cod. S. F. H. 



Lactophrys tricornis (Linnaeus) 



Small specimens were taken inside Bird Key reef. Larger ones were caught at 

 depths of 10 to 15 fathoms within and without the lagoon. Large ones were seen 



