188 DR. J. PEARSON ON MARINE FAUNA [Feb. 1, 



which have no posterior prolongations. Anteriorly each radial is 

 rod-shaped and the end is notched. The inter-radials also have 

 anterior prolongations, but these are not notched. 



The spicules agree with Theel's description. The spheres have 

 a diameter of 44 ju, and the cups have a width of 37 /.t. 



General distribution. Bohol, Java, Japan. 



Text-fig. 19. 



Colochirus cucumis. Calcareous ring. X 5. 

 r. = radial, i.r. = inter-radial. 



Thyone fusus, var. papuensis Theel. 



Thyone fasus, wax. papuensis Theel, 1886 (15) ; Pearson, 1903 

 (21). 



One specimen from Station XXXII. S.W. of Domel Is. 

 Total length 25 mm. ; greatest width 12 mm. 



This specimen has a characteristic appearance, being broad in 

 the middle and becoming suddenly much narrower at the anterior 

 and posterior extremities. Externally it resembles in a marked 

 degree the northern form Thyone fusus. Of the four recorded 

 specimens of the above variety, I have had an opportunity of 

 examining three, and I find that the only important difference 

 between the variety and the parent species is in the nature of 

 the calcareous ring. In both cases the shape is identical, but the 

 ring is much larger in the variety than in Thyone fusus. In the 

 specimen under examination the calcareous ring has a length of 

 12 mm., i. e. half the length of the body. In a specimen of Thyone 

 fusus examined by Theel, the calcareous ring was only one-fifth 

 the length of the body, and in a specimen I have examined the 

 ring was even shorter. 



The deposits agree with Theel's description, and appear to be 

 very similar to the deposits of Thyone fusus. In the Ceylon 

 specimens examined by me (21), there were tables scattered 

 throughout the general integument as well as the deposits in the 

 pedicels. In the Mergui specimen there are practically no 

 deposits in the general integument, but in the pedicels there are 

 tables similar to those described by Theel, and resembling those 

 found in the pedicels of Thyone fusus. 



Length of tables in pedicels 67 ji. 



Diameter of tables in integument (Ceylon specimen) 59 yu. 



General distribution. Torres Straits, Ceylon. 



