BY THE REV. J. E. TENISON-WOODS. 221 



jire the most highly organized members of it ; that is to say vermi- 

 form animals with a leathery skin in which calcareous granules, 

 plates and spicules are developed. There is no shell like the sea- 

 urchins, and it need not be said there is no back or belly in the 

 ordinary sense of the term. The so-called "teats" are usually 

 distributed in five rows, dividing the body into an equal number 

 of segments, but they may be partly or wholly wanting. They are 

 the ambulacral tube-feet, corresponding with the same organs in 

 star-fish, or in the poriferous zones of sea-urchins. Sometimes 

 these tube-feet are scattered over the whole body, or they are 

 restricted to what, for convenience, is called the ventral surface. 

 There is a long convoluted intestine, a special water-vascular 

 system ai-d a sand canal. The breathing is performed by a 

 respiratory tree or plume of arborescent tubes around the mouth. 

 In the family of Synaptidse there is no respiratory tree, and the 

 tube-feet are wanting, whilst the skin is furnished with calcareous 

 spicules of various shapes. The Synaptidee burrow in the mud or 

 sand, and the skin is furnished with anchor-shaped spicules, with 

 a little calcareous disc fastened loosely around the shafts of the 

 anchor. In Chirodotte the skin has minute calcareous wheels. In 

 the Oncinolabidse the skin has barbed spicules, and there are 

 tube-feet but no respiratory tree. 



It is a matter of regret to me that though I have seen a good 

 deal of tripang fishery in the Moluccas, Philippines, and Australia, 

 and know most of the commercial varieties which will be referred 

 to presently, I am unable to give any details towards their 

 zoological identification. The commoner species collected belong 

 to the genus Holothuria. Thus M. Dujardin (Hist. Nat. Zoophy., 

 Echinodermes) gives as the tripang specie.s, Holothuria edulis, 

 Lesson ; //. peruviana, Lesson ; //. ananas, Q. and G. ; but to 

 these must be added probably some of the genera Milllera, 

 titichopus, Psolun, Synapta, and some others. The order is divided 

 into (1) Apnetimona or sea-slugs, with no respiiatory tree, the tube- 

 feet wanting (Synaptidte) or present (Oncinolabidsu), and (2) Pneu, 

 monifera with a respiratory tree, such as Holothuria, Thyone- 

 Molpadia, Psolus, Cumineraria, &c. The genus Holothuria has 



