PLATE V. 



All the figures of this Plate, except figs. 30 and 31, represent different sections through the aurophore. 



Rhodalia miranda, n. sp. (p. 302). 



Diam. 



Fig. 24. Sagittal section through the aurophore and the neighbouring parts of the pneumatophore. 

 The thick wall of the pyriform medusoid aurophore contains a lacunar system of 

 wide irregular canals (Ir), separated by radial, irregularly branched septa. The auro- 

 stignia (lo), or the distal opening of the aurophore, leads into a narrow central axial 

 canal (la), and the proximal end of this auroduct, the auropyle (li), opens into the large 

 cavity of the pneumatocyst (pa). The auroduct is placed in the axis of a muscular cylin- 

 der, the pistil (Ijj), which fills up the subumbrellar cavity of the medusoid aurophore. 

 The pistil is surrounded by a thickened cylindrical cuticular vagina (If), seemingly the 

 distal prolongation of the pneumatocyst (pf). ps, Pericystic cavity (between outer, z, 

 and inner, z\ wall of the pneumatophore) ; ac, gastral canals of the trunk, traversing its 

 hyaline cartilaginous jelly-substance (z 1 ) ; z, fulcrum ; d, entoderm ; e, exoderm, . x 1 



Fig. 25. Frontal section (or vertical transverse section) through the basal part of the aurophore of 

 another specimen, la, Axial canal of the pistil ; le, its lining epithelium (exodermal) ; 

 Ip, longitudinal muscles of the pistil (seen in transverse section); If vagina pistilli 

 (cuticular tube); e 1 , exoderm of the inner wall of the aurophore (subumbrella?); e 2 , exoderm 

 of its outer wall (exumbrella 1) ; d, entoderm ; z, fulcrum : It; radial pouches and lacunar 

 canals, with radial septa between them. The upper part of the figure exhibits the insertion 

 of the aurophore at the dorsal base of ' the pneumatophore. pf, Pneumatocyst ; pa, 

 cavity of the pneumatocyst, . . . . . . . x 15 



Fig. 26. Frontal section through the middle part of the aurophore of the same specimen. The 



characters are the same as in fig. 25, . . . . . . x 15 



Fig. 27. A small fragment of the exumbrella (or the outer wall) of the aurophore, taken from the 

 transverse section, fig. 26. Two inner folds of the exumbrella are seen in vertical section 

 (through their fulcra! axis), e, Exoderm ; z, fulcrum ; d, entoderm, . . x 150 



Fig. 28. A small portion of a longitudinal section through the pistil of the aurophore. la, Axial 

 canal (auroductus) ; le, its epithelium ; lin, bundles of parallel, longitudinal, spindle-shaped 

 cells (apparently muscle-cells) ; In, their nuclei ; outside is the vagina pistilli (cuticular 

 tube, compare fig. 24), ......... x 300 



Fig. 29. Transverse section through a canal (ac) of the reticulum of the trunk ; the entodermal epi- 

 thelium (d) of the canal is simple, and surrounded by the hyaline structureless fundamental 

 substance of the cartilaginous support, . . . . x 150 



Fig. 30. A small portion of a vertical section through the pneumatocodon (or the exumbrella of the 

 pneumatophore). One of the simple or forked bands of entoderm-cells (rfj), which tra- 

 verse the cartilaginous fulcrum (z), connects the entoderm of the exumbrella (d) with its 

 exoderm (e), . . . . . . . . . x 150 



Fig. 31. Lateral view of the inferior part of the lamellar peduncle of a nectophore. The fine parallel 

 stripes (vertical in the figure) are horizontal (or radial) muscle-fibrillre (nm). A strong 

 prduneular canal (ns), arising from the trunk, runs along the inferior free horizontal 

 margin of the peduncle (right hand of the figure), and gives off a series of twenty to thirty 

 small, simple, secondary canals (nl). These ascend vertically ; their size decreases from 

 the inner (axial) towards the outer (abaxial) margin of the peduncle, . . x 15 



