220 Zoological Society : — 



Holothuria inhcBrens and H. Icevis, the first is a Synapta according 

 to the author's own definition. It was on this account that Prof. 

 Forbes referred our digitate species to Chiridota. 



However, subsequent authors have agreed to apply the name 

 Synapta to the species with anchors, which consequently adhere to 

 the finger * ; and to call those Chiridota which are ornamented with 

 microscopic wheels. In C. IcBvis these wheels are very minute and 

 clustered in little groups beneath the epidermis, and when the sur- 

 face is raised with a needle point they are set free. In Chiridota 

 violacea, figured by Miiller in the Berlin Transactions, and again in 

 Dr. Carpenter's ' Microscope,' the wheels are attached to a common 

 connecting thread. 



Prof. Steenstrup has formed a genus (or subgenus) for another 

 Greenland species — Myriotrochns Rinkii, in which the wheels are 

 larger and scattered over the skin, each having its own stalk. These 

 wheels first appear as little stars, with rays or spokes of various 

 number (18 to 2.5), which increase until they attain their normal 

 length, and then expand at their ends until they join and form a 

 rim (or tire) to the wheel. A ring of spines is afterwards formed 

 on the thickened margin ; the spines are pointed towards the centre 

 of the wheel, and are as numerous as, or rather more numerous 

 than, the spokes. As the wheels only occur on the three dorsal 

 intermuscular bands, they can scarcely assist in locomotion, and 

 must be regarded as ornamental characteristics, such as nature loves 

 to bestow for us to marvel at. 



Synapta, Eschscholtz, 1829. 



1. S. vittata (Fistularia), Forskal, 1/75. Suez, Red Sea. 



2. S. reciprocans, Forsk. Suez, Red Sea. 



3. S. inhcBrens {Holothuria), O. F. Miiller, 1781 ( = Holothuria 

 flava, Rathke ; Jemania Ilenslowana, Leach ; Synapta Duoerncea, 



Quatr.). Christiansand og Krageroe ; Aberystwith and Criccieth, 

 North Wales (Henslow and Wilton) ; Falmouth, Cornwall {W. P. 

 Cocks) ; Bantry, \V. Ireland (MacAndrew and Barrett) ; Guernsey 

 (E. C. Buckland) ; lies Chaussey, near St. Malo {Quatr ef ages). 



4. S. digitata {Holothuria), Montagu. Devonshire {Mont., 

 Cranch, Alder, Kingsley) ; Falmouth {Mr. Cocks) ; W. Ireland {Mr. 

 Barlee) ; Rothesay, Bute {Mr. Alder) ; Vigo Bay, N. Spain {Mac- 

 Andrew) ; Trieste {Joh. Miiller, Br. Hartmann). 



5. S. mamillosa, Esch. Tahiti. 



6. S. maculata, Chamisso & Eysenh., Act. Nat. Cur. x. p. 1. 1. 25. 



7. S. 1 verrucosa {Chiridota), Esch. Sitcha, Russian America. 



8. S. Beselii, Jager, 1833. Celebes. Berlin Trans, t. 6. f. 15. 



9. S. radiosa, Reynaud (teste Jager). Coromandel. 



10. S. bidentata, W. & B. 1858. China. 



W. S. lappa, Miill., Berlin Trans. 1854, t. 6. f. 1 6. W. Indies. 

 12. S. serpentina, Miill., id. f. 17. Celebes. 



* The name Fistularia, given by Forskal, has been abandoned, partly because 

 the author included under it some true Holothuria, and chiefly because Laniarck 

 employed it for these latter instead of the Synaptre. 



