Castle. — Rhynchobdellidae. 



PLATE 6. 



G. elongata. 



All figures of this plate were drawn from whole preparations. Annuli in Figures 

 23 a7id 27 are numbered from the posterior margin of the oral sucker backward. - 



Fig. 23. Head end viewed from right side. 



Fig. 24. Posterior end of body viewed from right side. 



Fig. 25. Brain, ventral view. 



Fig. 26. Brain viewed from right side. 



Fig. 27. Ventral view of entire animal partially contracted. In somites vii.-xxii. 



furrows between annuli are shown only at the margin of the body, 



except where they mark somite boundaries. 



