BE-CLASSIFIOATION OF MULLERIA AND HOLOTHURIA. 171 



This sub-genus contains a large number of species, of which 

 Halodeima atra (Jager) and Halodeima monacaria (Lesson) are 

 representative. 



Sub-genus THYsnosiCYA.* Sub-gen. nov. 



(= Holotliuria, Linn, partim ; Fistularia, Forskaal, 

 1775 ; Trepang, Jager, 1833, partim.) 



Twenty tentacles. Ambulacral appendages, papillae only, 

 which are often situated on wart-like eminences. Anal teeth 

 absent. Calcareous ring similar to that of Halodeima. 

 Spicules, tables, and buttons. 



This sub-genus contains a large number of species, of which 

 Thymiosicya impatiens (Forskaal) and Thymiosicya spinifera 

 (Theel) may be said to be typical examples. 



The following is a brief key to the sub -genera : — 



A. — Calcareous ring with well-marked bevelled ampullary 

 notches. The anterior border of the calcareous 

 rmg does not show the usual clear separation of 

 radials from inter-radials. The inter-radials 

 extend almost as far forward as the radials. 

 Spicules small, and taking the form of dichoto- 

 mously branched rods, or spinous rods, or both. 



{a) With anal teeth. 



Actinopyga. 



(h) Without anal teeth. 



Bohadschia. 



B. — Calcareous ring without well-marked ampullary 

 notches, and the anterior border is not bevelled. 

 The anterior border of the calcareous ring deeply 

 indented between the radials and inter-radials. 

 The radials generally extending much further 

 forward than the inter-radials. Spicules rarely 

 consist of perforated plates, generally consist of 

 tables and buttons. 



GutJLtOV = a wart ; ciV.oq — cucumber. 



