HOLOTHURIOIDEA OF THE INDIAN OCEAN. 53 



Bemarks. — This form has affinities with H. spinifera and 

 the related species. Nevertheless the large claw-like out- 

 growths on the sides of the body make the identification of 

 this form easy. But the two specimens under examination 

 are very different in external appearance, owing to the fact 

 that one specimen has undergone great contraction. 



HOLOTHTJRIA MACULOSA, n. Sp. 



(Plate VI., fig. 3.) 



One specimen from Aldabra, near He d'Esprit, collected by 

 Mr. J. C. F. Fryer. 75 mm. long. 



External Characters. — The specimen is evidently very much 

 contracted owing to its preservation in spirit. Hence the body 

 has a wrinkled appearance, and the ambulacral appendages 

 are in a contracted condition. The ambulacral appendages 

 consist of paj)ill8e only, which are irregularly scattered over 

 the whole body and show no arrangement with rows. The 

 colour of the trivium is chocolate-brown with a yellowish- 

 white circle 2 mm. in diameter around each papilla, thus 

 producing a distinctly mottled appearance. The white patches 

 seem to coalesce towards the posterior end of the body. 

 The same contrast of colours is presented on the bivium, 

 except that the brown is of a much darker shade, and is 

 present along the middle of the back as a series of irregular 

 patches which appear to be disposed in pairs. About five 

 pairs of such markings are discernible, the smallest being 

 about 8 mm. in diameter. In the same way the white does 

 not confine itself to the papillsej but in many places, especially 

 towards the posterior end, there are large patches of white. 

 Thus the bivium is not so regular in its markings as the trivium. 

 There are five groups of papillae around the anus. The tentacles 

 are not present. The integument is very hard to the touch. 



Internal Structure. — The calcareous ring is fairly large and 

 the radials are massive. There is one long PoHan vesicle and 

 one small stone canal on the right side of the dorsal mesentery. 

 The left respiratory tree is shorter but more voluminous, than 

 the right. Cuvierian organs are present. 



