162 A renicolidae 



account of its tubicolous habits, and of the feeble development of 

 its gills and the absence of statocysts, as forming a link between the 

 two families ; but, as already shown (p. 155), there is no doubt that 

 this genus is a member of the family Arenicolidae, though its habits 

 are similar to those of Maldanids. 



A consideration of the characters of the Arenicolidae shows that 

 this family has clear affinities with the Maldanidae, and also, but in 

 less degree, with the Scalibregmidae, and in still less degree with- 

 the Opheliidae. 



