HOLOTHURIOIDEA. 1!)5 



Tlie top of the spire is hemispherical and is covered by numerous spines (tin's. 22 

 and 23). 



The Ceylon specimen agrees very closely with Semper's description. Unfortu- 

 nately that author does not give any satisfactory account or figures of the spicules. 

 Theel found amongst the "Challenger" Holothurians one which he believed to lie 

 identical with Semper's species. The deposits in the " Challenger " specimen were 

 of two* kinds and differed considerably from those of the Ceylon specimen (see 

 Theel (7)). Seeing that there is this difference in the deposits, the "Challenger" 

 specimen and the Ceylon specimen cannot be identical. And yet the Ceylon specimen 

 agrees very closely with Sempek's original description. On the other hand, Theel 

 expresses some doubt as to the identity of the " Challenger" specimen with Semper s 

 species. Consequently I feel justified in assigning the Ceylon specimen to Semper's 

 species; and I suggest that the " Challenger" specimen be placed as a variety of the 

 species, which might be named var. theeli. 



Distribution : Philippines, Ceylon. 



Actinocucumis donnani, n. sp. Plate II.; tigs. 25-30. 



One specimen, from deep water off Galle (Stn. XL1.). 



It is 15 millims. long, and 9 millims. broad at the widest portion of the body. 



The colour of the spirit specimen is white. 



The body is in a contracted condition, so that the exact arrangement of the 

 pedicels is not very easy to determine. There appear to be, however, five series of 

 pedicels, each series consisting of four or five fairly straight rows. The dorsal rows 

 are more irregular than the ventral ones. Owing to the width of each of the five 

 series, the interambulacral spaces are very narrow. The pedicels have well-developed 

 sucking discs, and in the preserved specimen are very short and distinctly cylindrical. 

 Amongst the pedicels of both the dorsal and ventral surface there are scattered a few 

 papilla?, which are easily distinguished from the pedicels, because of their greater 

 length, their shape, and their delicate appearance. 



There are no anal teeth. 



Deposits : These are very thinly scattered, and consist of small oval perforated 

 plates (tigs. 26-28). In the pedicels there are numerous small slightly branched 

 bodies similar to those described by Theel as " incomplete rosettes" (figs. 21) and 30). 

 The pedicels have well-developed terminal plates. 



The calcareous ring is comparatively large, being 8 millims. long. Each of the five 

 radials is composed of two separate pieces, both of which are prolonged posteiiorlv. 

 The inter-radials are five in number. They do not extend so far anteriorly as the 

 radials, neither have they any posterior prolongations. The radials and inter-radials 

 are made up of a number of small pieces (fig. 25). 



* Semi>kr's species evidently had only one kind of tabic. 

 2 C 2 



