INTESTINAL WORMS. 



125 



neither do they scruple much, if other prey be scarce, to 

 eat their fellow-creatures. To accomplish this, the little 

 cannibals are gifted with a very curious kind of mouth ; 

 one, indeed, which has no parallel in any other race of 

 beings. This mouth consists of a long fleshy funnel, 

 plaited like a fan, which can be folded up or spread abroad 

 at pleasure. Should a worm approach, this funnel is un- 

 folded and applied around the body of its prey, which, 

 thus retained, in spite of all its struggles, is soon sucked 

 and emptied of its juices. 



" Another circumstance connected with the history of 

 these animals worthy of mention, is their great tenacity 

 of life. If a Planaria be cut in two, so trifling does the 

 occurrence seem, that either part moves on as if quite 

 unconscious of having lost its better half, and straightway 

 can repair the little inconvenience thus produced, the 

 missing portions soon growing again. 



" Nay, sometimes thej 7 divide spontaneously into two 

 animals, each of which, perfect in all its parts, evinces all 

 the powers of the original being." * 



An extraordinary creature was discovered by Dr Nord- 

 mann, infesting the gills of one of our commonest river 

 fishes — Cyprinus brama — and to which he gave the appro- 

 priate appellation of the Twin-worm (Diplozoon para- 

 doxuni). It is not more than one-fourth of an inch in 

 length, but consists of two bodies, precisely resembling each 

 other, united by a central band, exactly in the manner of 

 the Siamese youths, whose exhibition excited so much atten- 

 tion in England and America a few years ago. We might 

 have supposed that, like the human monstrosity in ques- 



* Jones's " Lectures on Natural History," i. 157. 



