VIII, D, 4 Wharton: Some Philippine Thalassemx 249 



In formalin the body is colorless, except the flattened posterior 

 end, which is white. 



There are 2 pairs of very small nephridia which open behind 

 the ventral setae. Owing to the smallness of the nephridia and 

 the poor state of preservation of these organs, the character of 

 the internal openings could not be determined. 



The anal trees are about 2.5 cm. long and rather broad and 

 sac-like. They are suspended from the body wall by muscular 

 filaments. The structure of the funnels could not be distin- 

 guished. A spherical, rectal diverticulum is present. 



The intestine was filled, except for the first 2 cm., with very 

 small sausage-shaped pellets of mud. 



Although this specimen is somewhat larger than T. formosulum 

 as described by Lampert, the number and position of the ne- 

 phridia, the arrangement of the longitudinal muscles, and the 

 general external appearance of the specimen seem to justify 

 identifying it as this species. 



Thalassema griffini sp. no v. 



Locality. — Port Galera, Mindoro. This species was first col- 

 lected on the inner side of Buquete Island in a soft blue sand- 

 stone rock just above low- water mark. The rock was honey- 

 combed with burrows made by a boring mollusk (Gastrochsena?) , 

 and the Thalassema was found in these old burrows along with 

 Gebia and other crustaceans. In order to get them out, it was 

 necessary to break up the rock with a crowbar. They were 

 found in this place in considerable numbers during the entire 

 time the station was occupied (March 12 to June 18). They 

 were also collected in great numbers on the outer side of the 

 island during most of the month of April. Here there is a 

 small cove with a rock bottom into which numerous shallow 

 potholes have been worn by wave action. These are partly filled 

 with sand, gravel, and small stones. Thalassema was collected 

 from the deeper holes. In one hole not over 60 cm. in diameter, 

 11 specimens were found and in another, 10, along with an equal 

 number of sipunculids. They seemed to lie directly on the rocks 

 with the sand and gravel covering them, and no definite burrows 

 or openings could be observed on the surface. On the 1st of 

 May they had entirely disappeared from this place, and could 

 not be found there during the remainder of our stay at the 

 station. 



Size. — The bodies of the largest specimens reach a length of 

 from 12 to 14 cm. when fully extended, with a diameter of from 

 10 to 12 mm. The proboscis varies in length from 5 to 8 cm. 



