REPORT ON THE ECHINOIDEA MORTENSEN 



287 



11.83° C; green mud and fine sand; August 5, 1909 (1 specimen, 

 Cat. No. E. 1314, U.S.N.M.). 



Station 5516; in the vicinity of northern Mindanao; Point Tagolo 

 Light, Mindanao, bearing S. 80° W., 9.7 miles distant (lat. 8° 46' 00" 

 N., long. 123° 32' 30" E.) ; 319 meters; bottom temperature 12.39° C; 

 globigerinae; August 9, 1909 (1 specimen, Cat. Nos. 1294, E. 1295, 

 U.S.N.M.). 



Station 5517; in the vicinity of northern Mindanao; Point Tagolo 

 Light bearing S. 83° W., 10.5 miles distant (lat. 8° 45' 30" N., long. 

 123° 33' 45" E.) ; 309 meters; bottom temperature 12.39° C; globig- 

 erinae; August 9, 1909 (3 specimens, Cat. No. E. 1282, U.S.N.M.). 



Station 5522 ; in the vicinity of northern Mindanao ; Point Tagolo 

 Light bearing S. 39° W., 6 miles distant (lat. 8° 49' 00" N., long. 

 123° 26' 30" E.); 420 meters; bottom temperature 11.28° C; globig- 

 erinae; August 10, 1909 (1 specimen). 



Station 5536; between Negros and Siquijor; Apo Island (C.) 

 bearing S. 26° W., 11.8 miles distant (lat. 9° 15' 45" N., long. 123° 

 22' 00" E.); 510 meters; bottom temperature 11.95° C; green mud; 

 August 19, 1909 (13 specimens, Cat. No. E. 1273, U.S.N.M.). 



Measurements 



Description. — The test is usually somewhat elevated above and 

 flattened below, sometimes also flattened above; the sides are regu- 

 larly arched, and the circumference is circular or more or less distinctly 

 subpentagonal. 



The ambulacra are usually distinctly sinuate. The interporifer- 

 ous zone is about twice the width of a poriferous zone. The mar- 

 ginal series of tubercles is very regular, only now and then there is 

 found a tubercle somewhat smaller or larger than the normal. The 

 marginal tubercles are in general rather small and inconspicuous, little 

 or not at all raised above the pore zone, whereas the interporiferous 

 zone is generally slightly sunken toward the mid line. The tubercles 

 are almost contiguous but there is still room left for some minute 



