213a 



APPENDIX. 



The delay which has taken place in the preparation of the coloured plates has enabled me 

 to make a few remarks on certain recent papers bearing on the subject. Several of these are by 

 A. F. Marion, who has already (p. 40) been alluded to as the discoverer of an hermaphrodite 

 Nemertean, which he found, with developed generative organs, in the month of March in the 

 Mediterranean. 1 



In a communication entitled < Histologic du Systeme nerveux des Nemertes' 2 the author 

 describes the lateral nerve-trunk as enveloped in a fine membrane, and gives an interesting 

 account of the fibres after they have entered the ganglia. He mentions that the nerve-cells in 

 the latter are chiefly elliptical and apolar, though multipolar are also present. He further 

 notes that in certain forms a pulpy granular mass occurs between the external sheath and the 

 internal fibres of the lateral nerve, probably referring to the fibro-granular matrix described on 

 page 110, and shown in Plate XXI, fig. 6, ri, of the present work. In these forms, moreover, 

 the cephalic ganglia are composed of the same pulpy mass, without a trace of cells. 



Another French author, M. Leon Vaillant, 3 next advances certain remarkable opinions con- 

 cerning contested points in the Nemerteans. He revives the idea, as he says, of Max Schultze 

 and De Quatrefages, that the proboscis is the digestive organ. The works of the latter author 

 have already been fully gone into, but I am unacquainted with the paper in which the former has 

 propounded this erroneous idea; indeed, the contrary opinion has been taken in the review of his 

 labours (see pp. 28, 29, &c). His assertion that the marginal stylet-sacs furnish the stylet 

 for the central apparatus through the ducts of the former organs has already been disposed of 

 (pp. 57 and 67). His remarks that the posterior chamber of the proboscis has an aperture leading 

 into "the general chamber of the body" (the proboscidian sheath being unknown), and that 

 Valencinia longirosiris (one of the Anopla) takes nourishment by the proboscidian aperture, 

 scarcely require refutation. 



A. F. Marion published an important article on the subject in his recent ' Recherches sur 

 les Animaux inferieurs du golfe de Marseille,' 4 which, indeed, mainly consist of an account of an 

 hermaphrodite Nemertean named Borlasia Kefersteinii, already alluded to in the " Zoography" 

 (p. 40). The form was dredged by the author at the above-mentioned locality amongst the roots 

 of sea- weeds, and, in conjunction with three other species of similar organization, its examina- 



1 ' Comptes Eendus/ torn. 69, 1869 



2 Ibid., torn. 68, 1869, p. 1474. 



3 ' La Revue scientifique de la France et de l'Etranger/ &c., 2e serie, 21st Sept., 1872. I am 

 much obliged to Mr. Waterhouse, of the Zoological Department, British Museum, for a perusal of this 

 note. 



4 'Ann. des. sc. nat./ v e ser., tome xvii, Nos. 3 & 4, 1st March, 1873. 



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