Diam. Pane 



PLATE LXI. 



Fig. 1. ACTINOMETRA PULCHELLA, Pourtulfes, Sp. 



Fiof. 1. A^ertical lono-itudinal section of an isolated disk. The section 

 passes tLrougli the edge of the mouth, which is seen just 

 in front of the large anal tube. The lobular structure in 

 the centre of the lower part of the disk beneath the fore- 

 gut is the plexiform gland, . . . . x 10 103 



Figs. 2-5. ACTIKOMETRA PARVICIREA, Mlill., sp. 



Fio;. 2. Vertical longitudinal section of the calvx and disk. The situa- 

 tion of the chambered organ between the centro-dorsal and 

 radials is well shown ; as are also the marginal position of 

 the mouth and the numerous coils of the digestive tube, 

 from some of which the epithelial wall has fallen away. 

 The labial plexiis is relatively large in the upper lip {i.e., 

 behind the mouth), but is inconspicuous in front of it, . x 7 103 



Fis. 3. Transverse section of an unorooved or non-tentaculiferous arm, 

 close to the base of a pinnule. The ventral surface is 

 flat, without any food-groove or tentacular apparatus, and 

 owing to the backward extensions of the ovaries below 

 their points of attachment to the genital cord, one appears 

 in section upon each side of the middle line (p. 110), . x 20 113 



Fig. 4. The upper part of a transverse section of a normal tentaculi- 

 ferous arm at the articulation of two joints, showing the 

 connection of the ovary and genital cord. In the coeliac 

 canal is a section of a parasitic worm, . . . x 25 133 



Fig. 5. Transverse section of the lower part of an arm just beyond the 

 attachment of a pinnule. On the left side are seen three 

 funnel-shaped water-pores, the inner ends of which lead 

 into the genital canal containing the triradiate genital 

 cord, X 27 9G 



Fig. 6. ACTINOMETRA NIGRA, r. sp. 



Fig. 6. Transverse section of an arm through the middle of a joint, 

 showing the branches of its axial cord. The genital canal 

 is occupied by a relatively large genital cord, and the 

 radial blood-vessel is well shown beneath the middle line 

 of the food-groove, between the ambulacral epithelium 

 and the water-vessel, . . . . . x 30 121 



