434 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



of this just about reaches the base of the second spine, which stands 

 on the edge of the adambulacral plates and is stouter, longer, com- 

 pressed, and truncate at the tip. This series is united by thick mem- 

 brane, and forms a serrate border to the furrow, the spines of one 

 side usually fitting into the intervals between the spines of the oppo- 

 site side. The spines of the same series are separated by a space 

 about equal to their own thickness. Just back of them is the third 

 spine, the bases almost touching, but as ^he outer spine is directed 

 away from the furrow it appears in the undried and uncleared speci- 

 men to be considerably spaced from the second. The adambulacral 

 plates are small, wider than long, and separated by an interval aJDOut 

 one-half their oAvn length. 



This species practises autotomy as shown by the comet forms, both 

 of which have the buds of 5 new rays. In one specimen two tiny 

 madreporites are visible. 



Type-locality. — Mauritius. 



Distribution. — Red Sea, Zanzibar, Mauritius, Mergui Archipelago, 

 Madras, Philippines, Molucca Islands, Timor, Torres Strait, north- 

 east Australia, New Zealand. 



Specimens examined. — Twenty-four : 



Specimens of Othilia purpurea examined. 



sta- 

 tion. 



5109 

 5158 



5159 

 5159 

 5159 

 5160 

 5164 

 5165 

 5165 

 6165 

 5165 

 5218 



6248 

 5249 

 6253 



Locality. 



25.8 miles SW. Corregidor Light, Luzon.. 

 Off Tinakta Island, Tawi Tawi Group, 



Sulu Archipelago. 



do 



do 



do 



do 



Off Observation Island, TawiTawi Group. 



do 



do 



do 



do 



Off Anima Sola Island, between Burias 



and Luzon. 



Gulf of Davao, Mindanao 



do 



do : 



Cataingan Bay, Masbate 



Depth, 

 fathoms. 



.do. 



Tataan Pass, Simaluc Islands, Tawi Tawi 



Group. 

 San Miguel Harbor, Ticao Island between 



Masbate and Luzon. 



18 



23 



28 



Seine, off 

 beach. 



do 



Shore , 



Nature of 

 bottom. 



Coral 



Coarse sand, 



shells. 

 Coarse sand... 



do 



do 



Sand 



Green mud 



Coral 



do 



do 



do 



Coarse sand . . . 



Coral 



Coral, sand. 

 Coral 



Num- 

 ber. 



No. 



of 



rays. 



No. of 

 madre- 

 porites. 



K-h?) 



(?) 



2 



(?) 



2 



2 



1 



2 



1 



2 



2 



2 

 2 

 2 



2 

 (?) 



Remarks. — Writers who have seen this species and the subsequently 

 described O. eridavella — notably Miiller and Troschel, Perrier, de 

 Loriol, and Koehler — do not say wherein the two differ. The range 

 of eridanella is coextensive with the eastern part of that of purpurea^ 

 while both forms have either 5 or 6 rays and 2 maderporic bodies. 

 The authors referred to above have recorded the species as follows: 



