REMARKS ON THE VERMES. 27 



their preservation in a fossil state. 3. The Nemertina 

 are white-blooded worms, like some of the Hirudina, 

 or leeches : in this group, however, the character of ar- 

 ticulation becomes most indistinct. Rudolphi has placed 

 Gordius along with Nemertes ; and if Gordius goes 

 into the group of Nemertina, it is possible that lularia 

 may also. Nemertes Borlasii is a long black sea-wornr, 

 which is said to suck shellfish ; and the articulations 

 of its body become visible when it is contracted.* 



(25.) Respecting the VERMES, or annulose worms, all 

 we can state in this place is matter rather of opinion than 

 of investigation. In a former volumef, we have felt no 

 hesitation in considering a large portion of Cuvier's Pa- 

 renchymata as belonging to the class of Testacea. We 

 have been led to this determination from the analogy of 

 Guilding's genus Herpa to that of Planaria; and from 

 the latter animals crawling upon a disk -shaped belly, per- 

 fectly like the Nudibranchia, or the dories and tritons, 

 ah 1 of which are universally considered as naked Mollusca. 

 On the other hand, we should be disposed to place 

 among the true Fermes all those in which the body, 

 from being cylindrical, presents no vestige of a disk. 

 Probably the greater part of the Entozoa of Rudolphi 

 come under this head ; they all live and propagate in 

 the interior of others, and they are so various that al- 

 most every animal has its own particular parasite. In 

 some of these, particularly in the order Nemato'idea, 

 there are no perceptible joints, but the external skin is 

 striated transversely: but as we ascend higher in the 

 scale, these incipient indications of the annulose struc- 

 ture disappear, and the body, as in the whole family of 

 the T&nio'idea, or tape-worms, is composed, as Cuvier 

 justly says, of joints more or less distinctly marked ; 

 the whole being terminated at one extremity by a square 

 head, hollowed by four small suckers, while the other 

 is attenuated to a narrow point. True it is, that both 



* Note on the Annelida ; Annals of Natural History, No. xvi. p. 385. 

 f Malacology, p. 37. 



