292 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 11 



cylindrical, dorsally partly papilliform or at least with smaller disk. 

 Internally, ring canal placed exceptionally far behind the calcareous 

 ring. Cuvierian organs present but apparently always small. 



Spicules an outer layer of tables with 4 to 8 marginal holes and 

 low spire, often with pillars slightly converging and few small spines on 

 the top. Buttons small, smooth, with six holes, usually smaller on the 

 ventrum, here becoming completely obliterated with age. Ventral feet 

 with end plate and almos't straight supporting rods with perforated ends, 

 or with a series of holes along the sides making them into elongate but- 

 tons. Dorsal feet with smaller end plate or none, and shorter rods, often 

 curved. 



Color white to gray with a varying amount of dark pigment flecks 

 or two rows of dark spots on the dorsum. Some individuals almost black 

 or covered by a reddish pigment, possibly from the mud in which they 

 live. 



Type: Possibly in Germany, 



Type locality: Bohol, Philippines. 



Distribution : Almost circumtropical, in shallow pools, usually con- 

 cealed in mud or sand. Common in the West Indies, including Bermuda, 

 as well as in Hawaii. In the Panamic region it has been found to range 

 from Ecuador to the upper end of the Gulf of California (30° N). 

 Extremely common in the Galapagos Islands, where 47 individuals were 

 secured at 17 stations. Also taken at Cocos and Clarion Islands. 



Depth: Shallow water, mostly hidden in mud or sand, rarely 

 among rocks. 



Specimens examined: A large number in various collections. In the 

 Hancock collections more than 150 individuals were examined, ranging 

 in size from 3 to 15 cm. 



Remarks: The material from the Panamic regions shows the same 

 lawless variation as that exhibited by the material from the West Indies. 

 Animals with two rows of dorsal spots occurred with others of the same 

 size in which minute specks of black were scattered over the entire 

 animal. As in material from other localities, one often finds no buttons 

 in the youngest individuals (few cm long), and in these the layer of 

 tables is better developed, with larger disk, complete circle of holes, and 

 a taller, more delicate spire. 



Steinbeck & Ricketts report the species as fairly common in the Gulf 

 of California and the Velero expeditions have proved that it is about the 

 third most common species in the Panamic regions, with the Galapagos 

 Islands being the place where it finds optimum conditions. From here it 



