1941 CATALOGUE OF FISHES OF TORTUGAS 209 



species concerned. The interpretation of the evidence makes the type of oxy- 

 brachius what oxybrachius promised to be, a synonym of distinctum. 



This fish is often common in its striped phase. It has in life a bluish-green 

 rather than a brownish cast, which, with the very white spot at the end of base 

 of dorsal, distinguishes it at once from other species of its own size. 



Reported by Jordan and Evermann (Bull. U. S. Nat. Mus., No. 47, pt. 2, 1898, 

 p. 1635) southward to Bahia, but on what authority is uncertain. Metzelaar's 

 specimens from Curasao are the southernmost ones known to me, ranging 

 thence to the West Indies and Florida. W. H. L. 



Sparisoma radians (Cuvier and Valenciennes) 



Scants radians Cuvier and Valenciennes, Hist. nat. poiss., vol. 14, 1839, p. 206 — Brazil. 



Scants lacrimosits Poey, Memorias, vol. 2, 1861, p. 422 — Cuba. 



r Scants atomarias Poey, Memorias, vol. 2, 186 1, p. 423 — Havana. 



Scants hoplomystax Cope, Trans. Amer. Philos. Soc, vol. 14, 1871, p. 462 — St.-Martin, 



West Indies. 

 Sparisoma xystrodon Jordan and Swain, Proc. U. S. Nat. Mus., vol. 7, 1884, p. 99 — Key 



West, Florida. 

 Sparisoma niphobles Jordan and Bollman, Proc. U. S. Nat. Mus., vol. 11, 1888, p. 551 — 



Green Turtle Cay, Bahamas. 

 Sparisoma pZavescens Metzelaar (part not of Bloch and Schneider), Trop. atl. Vissch., 



1919, p. 114. 

 Sparisoma radians Meek and Hildebrand, Field Mus. Nat. Hist., Zool. Ser., vol. 15, pt. 3, 



1928, p. 750, pi. 73, figs. 1, 2. 



As the abbreviated synonymy above suggests, this species has been much mis- 

 understood. Its power of great change in color and pattern and its sexual di- 

 morphism, as Meek and Hildebrand (see reference above) were first to point 

 out, make the recognition of its boundaries difficult. 



At Tortugas it abounds, and is found chiefly on or near the grass flats. 



The males are well marked by their dark-margined caudal fin, and by a narrow 

 blue line with a red one of the same width close behind it, both running from 

 eye to angle of mouth. A light blue opercular margin, with similar blue on pec- 

 toral base, marks the females, on the sides of which during the breeding season 

 at least an ill-defined reddish area behind the pectoral brightens their hues. There 

 is a minor difference in the transient phases of the sexes, as well as in their rela- 

 tively permanent markings. Both frequently show a median dorsal and an ocular 

 dark stripe. In the female a pectoral stripe of this pattern may be seen too, cer- 

 tainly more commonly than in the males. 



This fish also has a mottled phase. Fish which had become relatively quiet 

 under cover, without actually resting on the bottom, showed four dark dorsal 

 patches. A few scales darker than the others marked the location of these patches 

 sometimes when the fish was in motion, although at other times they disappeared 

 entirely. It changed almost immediately from gray to green when it passed from 

 sand into Thalassia planted over part of the bottom of an aquarium. Resting on 

 the bottom under the grass it was almost of a clear rich green, with a few incon- 

 spicuous mottlings of gray on the dorsal fin and at the level of the light line 

 separating the median and ocular stripes in the striped phase. 



