APPENDIX. 295 



whole yards of its unmanageable sinuosities in quest of food, or for 

 change of shelter, while its lesser fellows abandon their secret haunts, 

 as if to recreate themselves from the tedious restraint which the 

 presence of light has imposed upon them. Whether it be for obtain- 

 ing sustenance, — whether, if such be their nature, to seek a mate, — 

 whether to construct some curious edifice, whereof Heaven has made 

 them the innate architects, — or be it merely to sport amidst the 

 waters, — night is alike the season for excursions of enjoyment and 

 occupation, whereas the day of the upper world is devoted to rest. 

 Nay, so inherent is this instinctive nature, so evident this peculiarity, 

 that the sun has scarcely passed the meridian, when certain tribes 

 begin to betray their restlessness, and seem ready to put themselves 

 in motion." — Sir John G. Dalyell, Pow. Great, i. 41. 



" as she were waxed mad, 



And in meandered gyres doth wiiirl herself about, 

 That, this way, here and there, back, forward, in and out ; 

 And like a wanton girl, oft doubling in her gait, 

 In labyrinth-like tm-ns and twinings intricate." 



" There, as a line, their long dimension drew. 

 Streaking the ground with sinuous trace ; not all 

 Minims of nature ; some of serpent-kind. 

 Wondrous in length." — Milton, Paradise Lost, Book 7. p. 19. 



Lineus gracilis (page 26). 



Body cylindrical, of a dark umber colour with the exception of a 

 few narrow longitudinal white lines. The anterior portion is cor- 

 rugated transversely ; it is almost \ an inch in breadth, and tapers 

 from this very gradually to the terminal extremity. The anterior 

 extremity is slightly quadrilobate, and in the centre there is a small 

 foramen, through which a long, narrow, extensile, trumpet-shaped 

 proboscis can be protruded at the will of the animal. On each side 

 of this are two narrow longitudinal slits similar to those in Serpen- 

 taria. The edges, however, are more rounded, and consequently 

 not so closely applied to one another. The fissure behind, on the 

 abdominal surface, is small and rounded. — The power of dividing the 

 body spontaneously is not great. — H. D. S. Goodsir. 



Lineus lineatus (page 26). 



Body flattened, thick, linear-elongated, narrowed posteriorly, even 

 and smooth, of a uniform blackish-green colour on both surfaces, 

 excepting that the venter of the posterior part is sometimes ochre- 

 yellow. Head distinct, and separated by a stricture, small, quadrate 

 or semiovate, with a deep fissure on each side, a medial groove down 

 the vertex, and a shorter one opposite on the ventral side touching 

 the lip, where the four lines make a criicial figure. Rim of the 

 mouth white. Genital aperture large, ovate, with or without a pale 

 margin. Length 3-5" ; breadth 6'" ; thickness 2'". 



Specimens in spirits are wrinkled and rugose, with numerous very 



