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in the open sea or crawling along the bottom, or they pass their 

 life in burrows or definite tubes of various kinds." Amongst 

 other peculiarities, some species are polymorphic. " Claparede 

 was the first to show that Nereis dumerilii may occur in at least 

 five different mature forms; these differ from one another in size, 

 colour, mode of life, character of the eggs, &c." Fission and 

 gemmation and the regeneration of lost parts are not the least 

 uninteresting details of these in general beautifully-coloured 

 worms, which vie in hue with butterflies, but whose tints are far 

 more difficult to preserve. 



Earthworms and Leeches have become so associated with the 

 name of Mr. Beddard, and his ' Monograph of Oligochseta ' is so 

 widely known and generally consulted, that we might perhaps 

 confine our remarks by saying that this portion of the volume is 

 from his pen, and those of our readers who have recently read 

 the " Earthworm Studies " which are appearing in our pages, 

 will do well to consult this memoir also. The classification of 

 Leeches is evidently attended with some difficulty. As no fewer 

 than sixty-four colour varieties of the common Hirudo medicinalis 

 are said to exist, " it is not wonderful that the labours of some 

 systematists have been severe, and have provoked much criticism 

 and alteration on the part of others." We are not therefore 

 surprised at the remark of Sir J. Dalyell, which is quoted in a 

 footnote : " It does not appear that the history of the Leech 

 has advanced in proportion to the number of literati who have 

 rendered it the subject of discussion." 



Mr. Shipley has also written the account of " Gephyrea and 

 Phoronis." The Gephyrea are exclusively marine, and have 

 been the subject of considerable taxonomic discussion. They 

 were formerly associated with the Echinodermata; Lamarck 

 placed them near the Holothurians; and Cuvier "also assigned 

 them a position amongst the Echinoderms." Quatrefages re- 

 garded these animals " as bridging the gulf between the Worms 

 and the Echinoderms." The Sipunculids have a diet which 

 seems to consist almost entirely of sand, and, as Mr. Shipley 

 observes, " The enormous amount of sand and mud which passes 

 through the bodies of the Sipunculids shows that they must take 

 a considerable part in modifying the mineral substances which 

 form the bottom of the sea. Just as Earthworms, as shown by 



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