142 THE ZOOLOGIST. 



THE DISTRIBUTION OF BRITISH ANNELIDS. 

 By the Rev. Hildeeic Friend. 



By Annelids, as understood in the series of notes which 

 follows, we mean those earthworms and fresh-water worms 

 which are usually known as Oligochaets, or worms with few 

 bristles, to distinguish them from the Polychsets, which are 

 usually marine worms. As I am preparing a Monograph of 

 British Earth and Water Worms for the Ray Society, it seems 

 desirable that we should take a survey of our present state of 

 knowledge on the subject. As such a survey will require a 

 considerable space, it is thought best to begin with the larger 

 forms, which have been more fully "studied than the aquatic 

 annelids, and the whiteworms or Enchytrseids. In the present 

 paper I must be content to supply a list of those species of 

 earthworms which are now known to occur in various parts of 

 the British Isles. When Darwin published his work on ' Vege- 

 table Mould,' it was assumed that about ten species were in- 

 digenous. By steady work during the past twenty years I have 

 been able to quadruple that number, so that to-day we have 

 a total of something like forty species, subspecies, or well- 

 marked varieties. 



As earthworms are most readily distinguished by the position 

 of the girdle, I supply the numbers of the segments occupied 

 thereby, counting from the head, and reckoning the peristomium 

 (which has no setas) as the first segment. As nearly all earth- 

 worms have special pores, tubercula, or bands on the under 

 surface of the girdle, I give these also. When they extend over 

 consecutive segments, as in all the known species of Lumbricus, 

 the band is distinguished by the numbers joined with a hyphen. 

 When, as in Aporrectodea, there is not a band, but pores on 



alternate segments, a colon is used. Thus ^g. 32 indicates that 

 the girdle begins on the 28tb, and extends to the 33rd segment. 



