108 WORMS. MOLLUSCA. 4o. Detris. 41. Holothuria. 
Body hyaline, 2 2 inches long, with.am opake yellowifh belio 
covered with white pellucid gluten: za: enfiform, more than 
twice the length of the trunk, and furnifhed with a double 
femicordate fin. 
"» 
40. DERRIS, | Body dvinarien compofed 
: of articulations: mouth terminal; feelers 2. 
*Dunguinea Derris. 
| Yraafad. Linn. Spe. lii. p. 67. tab. 13. figs 1, 2. 
Inhabits the Coaft of Pembrokefhire. 
Body cylindrical, gradually tapering to a point behind, compofed 
;- of joints and capable of great flexibility ; covered with a mem- 
branaceous tran{parent coat, through which the internal parts 
» are vifibie: bead extended beyond the outer skin, lefs than 
‘the anterior part of the body, to which it is conne£ted by z 
membranaceous covering forming a neck : feelers white, fitu- 
ated at the top of the head, and eapable of being raiíed or 
deprefled at pleafure: mourh confifting of z lips, the upper- 
one hooked and moveable, the lower-one ftraight and fixed. 
It moves by an undulatory motion of the whole body. 
41. HOLOTHURIA. Body detached, cy- 
lindrical, thick, naked, and open at the 
extremity: mouih furrounded by ficthy 
branched tentacula or feclers. 
Thefe are afl inhabitants of the fea, and expand ar contract them- 
felves at pleafure: the anterior aperture ferves them both as 
a mouth and a vent, and from the hinder ong they reject 
Waters which had been Ladég: fucked in : the tentacula are 
retrattile, 
Elegans. With 20 branched tentacula : body pillows, above reddifh, 
" beneath white. . 
Mull. Zosl. Daj. NE tab. V. fig. ide 
‘Gunner AE. Scockb 1767- tab. 4. fig. 
lühabits the Northern Seai, and AM out water like a fiphon 
from the lower orifice: 8— 1 inches long. 
Body ‘varied with red and white: papi//z pointed diftant, thofe 
- of thc back difpofed in 6 rows: teutacula flefhy white, the 
tip furnithed with a tuft of fibres which. ate tuberculate 
within, 
1 
Fronggfa> 
