42 



ANATOMY AND PHYSIOLOGY. 



Fig. 1. 



ANATOMY AND PHYSIOLOGY. 1 



General Conception, or Archetype of a Nemertean. 



AKCHETYPE OF A NEMERTEAN. 



FlG. 1. In its ordinary condition. Fig. 2. In transverse section. 



a. Proboscis. ao. Aperture in snout for proboscis. d. Cutis en masse. e and e. Muscular coats of the body- 

 wall, f. Superior commissure. g. Inferior commissure. h. Ganglia. j. Digestive chamber. n. Lateral 

 nerves. o. Muscular sheath for proboscis. od. Proboscidian chamber containing corpuscles. p. Dorsal blood- 

 vessel, r. Lateral blood-vessels. ov. Ovaries. x. Muscular ribbons. 



1 A description of the anatomy of the group was published by the author in the c Transactions of 

 the Royal Society of Edinburgh' (vol. xxv) ; but so many additions, both in text and drawings, were 

 necessary, that this could not be allowed to stand. Accordingly the whole has been rearranged. 



