440 



MONTGOMERY. 



EXPLANATION OF PLATE XXIV. 



Fig. I. Lineus gesserensis : ganglion cell I. Sublimate, Del. haematoxylin + 

 eosin. 



Fig. 2. Ibid. : ganglion cells II. Sublimate, Del. haematoxylin + eosin. 

 Figs. 3-10. Ibid.: ganglion cells III. Sublimate, Del. haematoxylin + eosin. 

 Figs, ii, 12. Ibid.: ganglion cells III. Sublimate with acetic acid, Ehrl. 

 haematoxylin + eosin. 



Fig. 13. Ibid.: ganglion cell III. Flemming's fluid, Del. haematoxylin + 

 eosin. 



Fig. 14. Ibid. : ganglion cell III. Hermann's fluid, Ehrl. haematoxylin + 

 eosin. 



Figs. 15, 16. Linens sp.: portions of ganglion cells III. Sublimate, Del. 

 haematoxylin + eosin. 



Fig. 17. Cerebratulus lacteus : The two modifications of ganglion cells I. 

 Sublimate, Del. haematoxylin + eosin. 



Fig. 18. Ibid. : ganglion cells II, from the ventral side of the ventral brain 

 lobe. Sublimate, Del. haematoxylin + eosin. 



Fig. 19. Ibid. : an unusually large ganglion cell III from the dorso-ventral 

 brain commissure. Sublimate, Del. haematoxylin + eosin. 



Fig. 20. Ibid. : ganglion cell III from third commissure of the oesophageal 

 nerves. Sublimate, Del. haematoxylin + eosin. 



Fig. 21. Ibid.: ganglion cell III with two nuclei, from lateral side of ventral 

 brain lobe. Sublimate, Del. haematoxylin + eosin. 



Fig. 22 a-^. Ibid. : nuclei of ganglion cells III. SubUmate, Del. haematoxylin 

 + eosin. 



Fig. 23. Ibid. : ganglion cell intermediate between III and IV, from the 

 ventral side of the lateral chord. Sublimate, Del. haematoxylin + eosin. 



Fig. 24. Ibid. : part of a cross section of the ventral lobe of the brain, show- 

 ing the position of the first pair of ganglion cells IV of the brain. Obj. A, oc. 4. 

 Fig. 25. Ibid. : cross section of a lateral nerve chord, close behind the mouth 

 region, showing radial clusters of ganglion cells II. Obj. C, oc. 2. Sublimate, 

 Del. haematoxylin + eosin. 



Fig. 26. Ibid. : diagram to illustrate the regular arrangement of the cell 

 clusters of cells II {CI. II) and their respective openings (P.) in the inner neuri- 

 lemma, on either the dorsal or the ventral side of the lateral nerve chord ; X-X, 

 the imaginary median plane of symmetry. 



