KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 40. N:Q 4. 



families : Echiurida? [Echiurus and Thalassema], Bonellidre [Bonellia, Hamingia & Sac- 

 eosoma] and Epithetosomatidse [Epithetosoma]. To my thinking, it whould have 

 been niore in accordance with our idea of affinity, if they had proposed only two 

 families : Echiurida?, including the genera Echiurus, Thalassema, Hamingia and Bonellia, 

 and Saccosomatida? for the problematic genus Saccosoma. Their family Epitheto- 

 somatidse with its single genus requires its own chapter. 



According to my opinion the genus Epithetosoma has absolutely nothing to do 

 with the Gephyreans nor with their relatives. It is true, I have not had an oppor- 

 tunity of investigating the remains of this animal, if such remains really exist at 

 this date, and I am therefore reduced to relying solely upon the description and 

 figures of the two Norwegian investigators. Nevertheless, I dåre entertain the opi- 

 nion that my views may be acceptable. According to this opinion of mine Danielssen 

 and Koren had before them for investigation a Nemertean. Nothing in their own 

 text and figures seems to stånd in opposition to such a presumption. They charac- 

 terize the family Epithetosomatidae and its genus in the following manner: »Body 

 furnished with a cylindrical hollow tube, communicating with the perivisceral cavity. 

 Posterior to this tube, on either side of the anterior extremity of the trunk, a cleft, 

 or fissure, the bottom pierced with apertures. No bristles». Their * Generic Charac- 

 ter» is expressed as follows: »Body cylindric, fur- 

 nished at the anterior extremity with a long, non- 

 retractile, tubiform appendix (proboscis). Posterior 

 to the appendix, on the ventral surface, the round 

 buccal opening. On either side of the anterior ex- 

 tremity of the trunk, a cleft, or fissure, the bottom 

 pierced with several apertures. No anal appendi- 

 ces. The anus on the posterior extremity of the 

 trunk. > 



Epithetosoma norvegicum (after Danielssen and Koken 1891). 



Fig. 1. The animal magnified: a. the trunk; b, proboscis. 

 Fig. 2. Anterior extremity of the body; a. lateral fissures = ciliated 

 fossce of the Nemertean; b, buccal aperture; c, proboscis. Fig. 3. 

 The animal. opened dorsally. magnified: a, opening ou the inner 

 surface of the skin = pröbably nothing hut wrinM.es (Danielsses 

 and Koren wirte: »the bottom of this fissured opening was appa- 

 rently pierced with divers minute apertures, which, however, had 

 become so shrunk and contracted. that even under a powerful lens 

 tliey could not be plainly distinguished» ; b, oesophagus; c. an in- 

 striction. where the oesophagus passes into the intestine: d, folds 

 of the intestine = lateral dilatations; e, muscular bands passing 

 along the dorsal surface of the intestine = dorsal vessel?; f, the 

 uterus = the proboscis sheafh. Fig. 4. Anterior extremity of the 

 body. opened to show the apertures of the lateral fissures: a. apertures 

 = icrinMés; b. the orifice for the proboscis. magnified. 



