2 ,8 PAPERS FROM TORTUGAS LABORATORY vol. xxxiv 



By differences in color the sexes may be distinguished at least from the length 

 of 35 mm., and they are externally recognizable also by the differences in struc- 

 ture of the genitalia, as described under M. versicolor. 



The ovaries of the female are well developed in June, and breeding doubtless 

 proceeds throughout the summer. A "nest" was first discovered through the 

 behavior of the male parent, who guards the eggs. One was observed several 

 times slipping over and under a dead alga-covered gorgonian base. I moved 

 small pieces of dead coral lying near and so drew a swarm of Halichoeres to the 

 spot. They were set upon as anticipated. The bit of gorgonian might not be 

 approached without throwing the tiny fish into a fit of excitement. On micro- 

 scopic examination, clustered eggs, nearly spherical and about 0.8 mm. in 

 diameter, were found entangled in filamentous algae on its under surface. Each 

 egg had a tuft of threads attached to its membrane at either pole, more at one 

 pole than the other, serving to hold them where deposited. 



Deposition evidently occurs repeatedly at one spot, since within a circle about 

 25 mm. in diameter eggs were found in three distinct stages of development. The 

 youngest had a cap of cells at the attached pole, the next showed embryos reach- 

 ing four-fifths the way round the egg, and the oldest were near hatching. 



W.H.L. 



The collection contains 52 specimens, 27 to 49 mm. long. The dorsal and anal 

 rays were counted in 14 specimens, wherein the counts remain within the range 

 given elsewhere for 30 specimens; P. 14 or 15; scales 41 to 47. 



The following proportions are based on 4 specimens, 40 to 49 mm. long: Head 

 3.5 to 3.8; depth 3.7 to 4.3. Eye in head 3.2 to 3.4; snout 3.1 to 3.3; maxillary 3.3 

 to 3.9; pectoral 1.0 to 1.15. 



West Indies to Florida. S. F. H. 



Malacoctenus versicolor (Poey) 



This fish was noticed in beach rock on the east side of Loggerhead Key, under 

 one of the isolated coral heads on Bird Key flats, outside Bird Key reef, and on 

 eroded faces of the larger corals of Loggerhead bank. 



The pectoral rays are 14. Of 6 Tortugas specimens, 3 have D. XX,i2; A. IL21; 

 1 has an anal ray less, and another a dorsal and 2 anal rays less. The first 3 dorsal 

 spines decrease progressively in length, and because of the shortness of the 18th 

 there is a second depression in the fin. A bifid cirrus at the anterior nostril usually 

 present; also a bifid or trifid ocular cirrus with its longest element about equal to 

 diameter of eye ; a comb of 6 cirri ; scales 8-55-18. 



Outstanding elements in the color pattern are six brown bands on the sides, 

 narrower below, darker and more nearly solid in color in the male, lighter in the 

 female and more broken by ground color; the anterior ones continuing more or 

 less plainly on dorsal fin. The sexes are readily distinguished in life by the red 

 ground color of the male, and the straw or cream color of the female. The female 

 alone has the dorsal, anal, and caudal rays spotted. 



Besides being distinguished by differences in color, the sexes, like those of 



