258 HAWAIIAN AND OTHER PACIFIC ECHINI. 



Station 2984. Off Guadeloupe Island, Mexico; 28° 57' 15" N., 118° 15' 45" 

 W. Bott. temp. 49.8°. 113 fathoms. Gy. s., brk. sh. 



Bathymetrical range, 20-113 fathoms. Extremes of temperature, 59°-49.8°. 

 Four hundred and fourteen specimens. 



Lytechinus semituberculatus Verr. 



Echinus (Psammechinusj semituberculatus Agassiz and Desor, 1846. Ann. Sci. Nat., (3), VI, p. 368. 

 Lytechinus semituberculatus \'ernll, 1867. Trans. Conn. Acad., I, p. 301. 



Now that it has become clear that Psammechinus pidus Verr. is quite distinct 

 from this species, it would seem that semituberculatus is not found on the con- 

 tinental coast, but is confined to the Galapagos Islands. All of the specimens 

 taken by the "Hassler" and "Albatross" are from the Galapagos, nor did the 

 collectors on those vessels meet with it elsewhere. The extensive collections of 

 Echini from Lower California and Mexico, studied by Verrill and Liitken con- 

 tained no specimens, and there are none in the M. C. Z. collections from the 

 mainland coast. The bright coloration is very distinctive and seems to be quite 

 constant. It is much nearer that of some West Indian specimens of variegntus 

 than it is to the dull shades of pictus. 



The "Albatross" took this species at the following places: — 



Hood Island, Galapagos. 



Indefatigable Island, Galapagos. 



Station 2810. Off Hood Island, Galapagos; 1° 22' S., 89° 39' 30" W. 6.5 

 fathoms. Co. s. 



Fourteen specimens. 



Lytechinus pictus, comh. nov. 



Psammechinus pictus Verrill, 1867. Trans. Conn. Acad., I, p. 301. 



Plates 99, figs. 6, 7; 107, figs. U-I4. 



The scries of specimens collected by the "Albatross," taken in connection 

 with those which have gradually accumulated in the M. C. Z. collection, enables 

 us to give tlii.s species its rightful place. Xorrill's original description is suffi- 

 ciently complete so that it is unnocossary to repeat its details, but since its main 

 points have been obscured li>' his consitlcring a large sjiecimen of TojoptieuMes 

 roscus as an adult pictus (/. c. p. 581), it seems desirable to give figures of this 

 interesting species and to discuss some of its characteristic features. 



