WORMS. 129 



The last group of Worms here represented is that of the 

 Gephyria (94, 135-144) ; with the advance of our knowledge it is 

 probable that they will be found to be more intimately allied to the 

 Annulata than is now generally supposed ; it will be seen indeed 

 that Echiurus has bristles at its hinder end ; Sipimculus is the best 

 known representative of the unarmed Gepliyria ; Bonellia is inter- 

 esting both from the fact that it owes its green colour to a matter 

 closely resembling the chlorophyll of green plants, and from the 

 possession by the female of a proboscis, Avhich is protruded from 

 the hole in the rock occupied by the worm : the male is very much 

 smaller than the female, and is not nearly so well developed. Owing 

 to the mode of lighting the Gallery, the visitor may have to shift 

 his position several times before gaining a good view of the whole 

 length of the proboscis. 



K 



