PLATE LX. 
The Lettering is the same in all the Figures. 
a’. Ventral branch of the axial cord of the arm. | gv. Genital vessel. 
ad. The parambulacral extensions of the axial-cords into the | ib. Intervisceral blood-vesse 
ventral perisome of the disk, lp. Labial plexus. 
ae. Ambulacral epithelium. | nm. Ambulacral nerve. 
b. Radial blood-vessel. nr. Its oral ring. 
c. Bands of connective tissue in the body-cavity. p. Pigment granules. 
ec. Coeliac canal. sa, Sacculi. 
eve, Circumvisceral coelom. | so. Spongy organ. 
e, External epithelium. ste. Subtentacular canal. z 
Sg. Fore-gut. tb. Tentacular branch of water-vessel. 
g. Epithelium of the gut. | w. Radial water-vessel. 
ge. Genital cord. wp. Water-pore. 
gc’. Genital canal. | wt. Water-tube. 
Diam. 
Fig. 1. Transverse section of an ambulacrum behind the mouth, show- 
ing the connection of the genital vessels (gv) and labial 
plexus (/p), : : ; ; ee Pe) 
Fig. 2. Anrepon carrinata, Leach, sp. 
Fig. 2. Portion of a vertical transverse section of the disk in the anal 
interradius, showing the connection of the genital vessels 
(gv) and labial plexus (/p), : . bd 28a 
Figs. 3-6. ANTEDON ESCHRICHTI, Miill., sp. 
Fig. 3. Portion of a vertical longitudinal section of the disk, which 
passes through the peristome, showing the connection of 
the intervisceral vessels (‘b) with the spongy organ (so), . x 35 
Fig. 4. Longitudinal vertical section of the peristome in the direction 
ofaray, . : : : : 2:5) X* NGO 
Fig. 5. Part of a vertical transverse section of the disk in the anal in- 
terradius, showing the spongy organ and labial plexus, . x 40 
Fig. 6. Transverse section of a brachial ambulacrum, showing one of 
Fig. 1. ACTINOMETRA PULCHELLA, Pourtales, sp. 
the ventral branches of the axial cord (a’)' which extend 
into the perisome at the side of the food-groove, . oe eS 
1 This is wrongly lettered ad. 
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