PLATE VI. 



Colours: see Plate I. 



Figs. 



1 80 — 203. Chaetoderma Loveni. 



Figs. 202, 203. 



Chaetoderma Loveni, drawn from spirit-specimens. 4 X. 



Posterior extremity witli the long straight spicula. 37 X. 



Spicula 75 X. A of the body-wall, .ff around the mouth-opening, Cof the posterior extremity. 



Section through the integument. 125 X. R "Riesenzellen". 



Section through the integument of the middle region. 215 X. 



Schematic transverse sections through the anterior extremity, c "Mundschild", a see text, 

 in lateral, w' dorsal, i/i" ventral retractors. 30 X. 



Sections through the radula of one of the specimens. 215 X. See text. 



Sections through the radula of the other specimen. 215 X. Sec text. 



Schematic transverse section through the middle region of the animal. 30 X. / liver, 

 / intestine. 



Schematic transverse sections through the posterior extremity. 39 X. _§■ gills, ^w/ gill- 

 protractor, t'r ventral retractors, dr dorsal retractors, /;■ lateral retractors, ^/j ganglion 

 posterius superius. 



Section through the pericardium, in which the ganglion posterius superius G.p.s. natrium, 

 dr dorsal retractors. 75 X. 



Sections through the cerebral ganglion kg, 7, ./, j, 6 lateral ganglia, /. 2 proximal 

 ganglia. 50 X. 



Figs. 204 — 210. Chaetoderma Wireni. 



Fig. 

 Fig. 

 Figs. 



Fig. 

 Fiffs. 



204. Chaetoderma Wireni, drawn from the spirit-specimen. 4 X. 



205. Spicula. 75 A of the body-wall, B of the posterior extremity, C around the mouth-opening. 

 206, 207. Schematic transverse sections through the anterior part 29 X. in dorsal retractors, vi lateral 



retractors, m" ventral retractors. 

 208. Section through the integument. 125 X. 

 209, 210. Sections through the radula. 215 X- See text. 



Figs. 211 — 216. 



Fig. 211. Radula of Chaetoderma canadense. 215 X. See text. 



Figs. 212, 213. Radula of Chaetoderma sp. (NoRMAX). 388 X. See text, tc tongue-cartilage, ;// muscle, | 



s g sublingual ganglion, E ciliated epithelium of the pharynx. 

 Figs. 214, 215. Radula of Chaetoderma sp. (=: Chaetoderma Loveni). 215 v. See text. 

 Fig. 216. Radula of Chaetoderma nitidulum. 215 X. See text. 



