HISTOKY OF THE SUBJECT. 11 



the animal is seen on its edge) a conspicuous lateral fissure. It appears to be related to Mlcrura 

 fuse a. 



In 1780, Otho Fabricius, 1 following 0. F. Muller, placed the Nemerteans in the genus 

 Planaria, under his sixth Class "Vermes/ 5 He mentions Planaria angidata, P. rubra, 

 P. viridis, P.fusca, P. caudata, and P. Candida, most of which had been previously described in 

 the ' Zool. Danic. Prodr/ of O. F. Miiller. Under the head of Planaria fusca {Lineus gesserensis) 

 he corrects certain statements of the latter author, who had only seen spirit-preparations. He con- 

 sidered the aperture of the proboscis to be the mouth, and the tube itself the intestine. He also 

 noticed that it lived in numbers under stones. 



Linnaeus seems to have had little or no acquaintance with Nemerteans, which were either 

 unknown or confounded with other animals, and it was only after the labours of O. F. Muller and 

 others had brought them into view that they were noticed in Gmelin's edition of the ' Systema 

 Naturae/ 3 published in 1788. They were grouped by Gmelin along with the Planarians under 

 the Genus Planaria, one of the divisions of his Class Intestina. They thus became associated 

 with intestinal worms, Lumbrici, Sipuncnli, and leeches. They were classified as follows : — (1) 

 Those without eyes -, (2) those with one eye ; (3) those with two eyes ; (4) those with three eyes ; 

 (5). those with four eyes ; (6) those with many eyes. The animals, however, were so little under- 

 stood that this arrangement is not to be depended on. Nothing new was introduced in Dr. 

 Turton's translation of this edition of the c Systema.' 3 



Otho Fabricius, returning to the subject in 1798 described 4 three Nemerteans under the 

 names of Planaria angulata, P. fuscescens, and P. Candida, from Greenland. Like Pallas he 

 considered the proboscis to be the alimentary organ, though he correctly interpreted the mouth 

 in the Lineidce, and the anus in both. 



In the following year, 1799, Jens Rathke 5 alludes to six species of the group, viz., Planaria 

 badia, P. lateritia, P. sanguinea, P. carnea, P. atrojmrpurea, and P. linearis. The first two I 

 have not satisfactorily made out, the third probably refers to Lineus sanguineus, the fourth to a 

 variety of L. gesserensis, the fifth may be L. marinus, while the sixth is Cephalothricc linearis. 

 Three of the species are figured. 



Lamarck, in his ' Systeme des Animaux sans Vertebres ' 6 mentions only one Nemertean, viz., 

 the Planaria rosea of O. F. Muller. 



L. A.'G. Bosc 7 classified the Nemerteans with the Planarians under the true worms with 

 elongated articulated bodies, but without external organs, placing them with the Gordii and 

 leeches. In regard to species he follows 0. F. Muller. 



Montagu was the next British naturalist after Borlase who paid attention to the Nemer- 

 teans. 8 In 1804 he gave a good superficial description of the worm mentioned by the 

 former, under the name of Gordius marinus 3 W\t\\ remarks on its habits. He was, moreover, the 



1 Otho Fabricius, ' Fauna Grcenlandica/ Hafnia3 et Lipsize, 1780. 



2 Gmelin's, l Linnseus Syst. Nat./ torn, i, pars, vi, p. 3087. Leipsise, 1788. Editio decime tertia, 

 aucta, reformata. 3 London, 1802. 



4 c Skrivter af Naturhistoire Selskabet/ 4de bind, 2det hefte, p. 52 et seq. Kiobenhavn, 1798. 



5 ' ' Jattagelser henhorende til Jndvoldeormenes og Blddyrenes Naturhistoire." < Skrivt. af Natur- 

 hist./ Selsk. v, 1 heft., pp. 83, 84. Kiobenhavn, 1799. 



6 Paris, 1801. 7 < Hist. nat. des Vers. 5 Paris, 1802. 



8 ' Description of several Marine Animals found on the South Coast of Devonshire/ Trans. Linn. 

 Soc., vol. vii, pp. 72 and 73. 



