AGASSIZ AND CLARK: REPORT ON ECHINI. 249 



internal pillars, and the color. It also resembles somewhat, young specimens of 

 C. humilis, but is readily distinguished by the narrow poriferous zones, wide open 

 petals, and very narrow interambulacra. The test is ovate, very flat and thin, 

 with the actinostome little sunken and the petaliferous area abruptly, but slightly, 

 elevated. The petals are short, broadly ovate, widely open distally and with very 

 narrow poriferous zones. There are five genital openings. The primary spines 

 are rather long and their tubercles contrast decidedly with the not very numerous 

 miliaries. The walls of the test are thin and there are three or four concentric 

 series of very flat, thin vertical pillars forming interrupted walls, occupying the 

 distal fourth of the interior, much as in Laganum. But there is also, in each in- 

 terradius, as in most true Clypeasters, a group of four or five pillars near the 

 actinostome, and there are numerous, though minute, needle-like projections on 

 the actinal floor. The specimens range from 6 to 38 mm. in length. The largest 

 is 31 mm. broad and 7.5 mm. high ; the test is only a little more than 3 mm. thick 

 at the margin. The petals are subequal, 9 mm. long and a trifle over 5 mm. 

 broad, but the poriferous zones are considerably less than a millimeter in width. 

 The posterior lateral interambulacra are less than half as wide at the ambitus as 

 the ambulacra on either side of them, though in smaller specimens they may be 

 three-fourths as wide. In color the specimens vary from bright yellow, or 

 reddish-yellow, to dirty purplish-white. The yellow specimens have a large 

 number of rather indistinct, dusky blotches on the abactinal surface. These are 

 arranged in pairs, four pairs in each ambulacrum and interambulacrum, and form 

 four concentric circles around the petals, parallel to the margin of the test. In 

 all the specimens there is more or less contrast in color between the ambulacra 

 and interambulacra on the actinal surface. 



Station 3823. Off Lae-o Ka Laau Light, Molokai, 78-222 fathoms. 

 3987- Off Hanamaulu, Kauai, 50-55 fathoms. 



" 4046. Off Kawaihae Light, Hawaii, 71-147 fathoms. 



" 4064. Off Kauhola Light, Hawaii, 63-107 fathoms. 



" 4066. Off Ka Lae-o Ka Ilio Point, Maui, 49-176 fathoms. 

 Fifty-seven specimens. 



LAGANIDAB Des. (Emended). 



Laganum fudsiyama D6d. 



Laganum fudsiyama Doderlein, 1885. Arch. f. Naturg. Jahrg. 51, Bd. 1, p. 104. 



A large series of this species was collected. Most of them have the superficial 

 appearance in miniature of specimens of Clypeaster Ravenellii A. Ag., the centre of 

 the test is so considerably and abruptly elevated. The amount of elevation is, 

 however, quite variable, ranging from 25 to 40 per cent of the long diameter. 

 The smallest specimen measures 8x8 mm. and the largest 50 x 46. The color 

 is usually green, but ranges from grayish-yellow to rich, deep green. Oftentimes 

 the ambulacra, on the actinal side, are more or less colored with dark purplish- 

 brown. 



