18 HISTOEY OF THE SUBJECT. 



identical with the British forms. They correctly interpreted the mouth in the Anopla, but 

 erroneously considered the aperture of the proboscis a genital pore, representing, moreover, as 

 a parasite (Plate m, fig. 14) the proboscis escaping from the mouth of a specimen of Borlasia 

 tricuspidata. A Tetrastemma, with a deeply notched snout and four large eyes (" Borlasie a 

 quatre points"), which they took in the sea, near Amboyna, was found inhabiting an Anatifa, 

 but whether it occurred there accidentally or otherwise we are not informed. The worms are 

 placed under the Zoophytes in the group " Vers Apocles." l 



In 1838 Dr. George Johnston published further interesting observations on the genus 

 Nemertes? mentioning nine species as occurring on British shores. His general anatomy 

 remains as before, the proboscis being described as the alimentary organ; but he rightly 

 observed that one section of the worms had and another had not stylets in the proboscis ; and 

 accordingly this formed the basis of his classification. He termed the true alimentary chamber 

 the general cavity of the body, though he qualified this description by saying that the 

 lateral cseca were parts of the digestive system. He also observed that the ova were independent 

 of these cseca, and were developed between them and the skin. He, however, thought the 

 mouth in Linens sanguineus a nerve-ganglion, and in the entire group called the ganglia 

 "hearts." He discovered the gregariniform parasites infesting Lineus, though he could not 

 make out their nature. Two plates of very fair figures accompany this paper, from the pencil 

 of his accomplished lady. If M. de Quatrefages found that his species — Folia purpurea, ' Voy. 

 en Sicilie/ ii, p. 122 — approached very closely the Nemertes or Borlasia purpurea of this author, 

 it must have belonged to the Anopla, and have had lateral fissures. 



W. S. Macleay, in his remarks on the Annelida in Sir R. Murchison's ' Silurian System ' 

 (1839), considered the Nemerteans as aberrant annelids, classifying them along with the 

 Lumbrici and leeches, under the group Apoda, in which the body was without a distinct head 

 or feet. The " Nemertina " were further characterised as aquatic, without eyes or antennae, and 

 with indistinct articulations, which, indeed, were only visible in contraction. Special reference 

 is made to the long vermiform impression in the Cambrian Bocks of Llampeter, which is termed 

 Nemertites Ottivantii, Murchison ; but, so far as I can judge from the description and plate, this 

 is a very doubtful Nemertean. 3 



In 1840 Professor E. Grube 4 made some observations on the Nemerteans of the Adriatic, 

 describing several species, two of which are figured, viz. Folia delineata, Delle Chiaje, and 

 Meckelia annulata, Grube. The latter, however, is the Notospermus drepanensis of Huschke ; 

 and, while I am not acquainted with the Borlasia annulata of Ehrenberg, another which he 

 mentions, his Borlasia viridis appears to be allied to Lineus gesserensis. Under Ehrenberg's 

 name Amphiporus, he also refers to what, in all probability, is an example of the Enopla ; but 

 the identity of this form, or the succeeding new eyeless type Akrostomum Stannii, Grube, cannot 

 be determined. This veteran investigator of the annelids and their allies recognised the 

 correct situation of the apertures of the proboscis, mouth, and anus. He observed that the 



1 ' Voyage de decouverts de 1/ Astrolabe — sous le commandement de M. J. Dumont D'Urville/ 

 Zoologie, par MM. Quoy et Gaimard, tome quatrieme. Paris, 1833. 



2 cc Miscellanea Zoologica," 'Mag. Zool. and Bot./ vol. i, pp. 529 — 538, pis. xvii and xviii. 



3 Murchison's ' Silurian System/ vol. ii, p. 699, pi. xxvii, f. 4. 



4 'Actinien, Echinodermen und Wiirmer des Adriatischen und Mittelmeers/ pp. 57 — 60, figs. 

 7, 7 a, 8, and 8a. Konigsberg, 1840. 



