SEA-WORMS. 123 



our clumsy fingers could do nothing with them ; but you must 

 be prepared for this, and bring with you a clean camel's hair 

 brush. With this you can pick them up, and by dipping it 

 into a jar of sea- water, and giving a quick rotatory motion to 

 the brush, the Planarian will be dislodged, and will probably 

 settle on the side conveniently for your examination of it with 

 your lens. Any slimy-looking spot of colour that appears upon 

 a stone or sponge you should attempt to move with your 

 brush, and in many cases it will prove to be a Planarian- 

 that may afterwards so expand as to surprise you with its 

 beauty. 



Sir John Dalyell, many years ago, described how he cut up 

 a specimen of the common Black Planaria (P. nigrd) of our 

 fresh-water ditches, each portion of which became a complete 

 animal; and upon this slender basis appears to have been 

 founded the statement, which is copied in all the books, that 

 worms of this class partly propagate by spontaneous division, 

 in addition to their interesting egg-laying. 



Dr. Collingwood, who has paid considerable attention to 

 this comparatively neglected group, doubts this, and I think 

 with good reason. He has never seen this division take place ; 

 and I would humbly add that I have kept large numbers of 

 the fresh-water species for years, but never observed the 

 phenomenon, though I have carefully watched for and really 

 expected it to take place as such fission undoubtedly occurs 

 in the Sea-anemones. 



One of the largest and most conspicuous of our native 

 species is the Banded Flat- worm (Enrylepta vittata), which is 

 marked with longitudinal black lines on a whitish ground. It 

 has a pair of tentacles in front of the broad, flat body, which 

 gradually tapers away to a point behind. It has a large 

 mouth opening near the centre of the underside. 



A more worm-like group is the Nemertea, which is divided 

 into genera, founded on the number or absence of eye spots. 

 One of these is the Red-faced Blind-worm (Astemma rujifrons)> 



