HISTORY OF THE SUBJECT. 19 



former had a special sheath, and that it was not connected with the alimentary system, which 

 lay beneath it. 



During the same year (1841) the valuable 'Descrizione e Notomia Animali Invertebrali/ 

 of Delle Chiaje, was published at Naples, containing further and important observations on 

 the Nemerteans. It has, indeed, been aptly said by the lamented Professor Claparede, that the 

 productions of this author form zoological mines, from which succeeding investigators may quarry out 

 much that is new and rare. In this fine work the author describes the Nemerteans as Annelosi 

 Folici, and considers they offer certain analogies with the leeches, on account of the structure of 

 the alimentary canal, while in the form of their bodies they approach the Planariae. A good 

 description is given of the digestive tract and its "hepatic sacs/ 7 with their varying arrangement, 

 e.g. " pinnatifid-bifurcate " in Folia delineata, and bifid in Folia rosina ; but he falls into the 

 error of regarding the stylet-region of the proboscis in the Enopla as the stomach, and exhibits an 

 imperfect and inverted figure of the region (Tab. 104, fig. 22; vol. v, p. 42) in the Frostoma 

 candidum of Duges. He, however, correctly interpreted the relations of the proboscis to its 

 sheath, the anatomy of the generative organs, and showed an elaborate series of branching 

 transverse arteries between the dorsal and lateral vessels in Folia sifoncello. Many species are 

 described and figured, and for the first time he notices the semi-parasitic habits of Folia tetrqph- 

 t/mlmata, which he found in the respiratory cavity of " Ascidia mammellata" Besides the new 

 species, the descriptions and remarks concerning the old enable us to determine more clearly 

 their nature and relationships. 1 



Mr. W. Thompson 3 contributed at this time, under the head of " Additions to the Fauna 

 of Ireland/' an account of some species of Nemerteans, viz. Nemertes gracilis, JV. lactiflorea, 

 Carinella trilineata, and Gordius annulatus. The two latter refer to the same species, viz. 

 Carinella annidata, the one being Dr. Johnston's name, the other Montagu's prior title. 



In P. Gaimard's c Voyages en Scanclinavie, en Laponie/ 3 &c, considerable attention is 

 devoted to the Nemerteans; but, as only the plates of this work could be procured in the 

 British Museum, its examination is incomplete. However, as none but he who is conversant 

 with the anatomy of the parts can correctly represent in a drawing so minute and complex 

 structure as is found in the proboscis of the Enopla, we may with propriety make a few remarks 

 on these plates. In Plate c, most of the figures, from 1 to 20, seem to pertain to Amphiporus 

 pulcher, and therefore the slit which is shown behind the ganglia in fig. 9 is erroneous. The 

 entire animal is well represented in fig. 20. Figs. 23, 24, and 28 belong to a species resembling 

 Nemertes gracilis. Fig. 1 of Plate d would do for Amphiporus lactifloreus. The whole of Plate e 

 is devoted to the Nemerteans, and in this the structure of the proboscis of the Enopla is detailed. 

 In Plate f a curious form is delineated (figs. 1 and 3), with a spear-shaped snout, a flattened 

 body and widened tail. It appears to be an intermediate type between the Nemerteans and 

 Planarians, and probably is a swimmer. The drawings were made by G. Boeck. 



(Ersted, 4 in the fourth volume of ' Kroyer's Naturhistorisk Tidsskrift' for 1842-43, wrote 



1 ' Descrizione e notomia animali invertebrali della Sicilia citeriore osservati vivi negli anni 1822— 

 1830/ da S. Delle Chiaje. Napoli, 1841. 



2 ' Ann. Nat. Hist./ vol. vii, 1841. p. 482. 



3 'Voyages de la Commission Scientifiqne duNord en Scandinavie, en Laponie, au Spitzberg et aux 

 Feroe, sur la corvette La Recherche.' Paris, 1842, &c. 



4 Kroyer's ( Naturhistorisk Tidsskrift/ Fierde Bind. Kiobenhavn, 1842—1843. 



