PLATE L. 



Compare figs. 7-12 in PL XLIX. 



Disconalia gastroblasta, u. sp. (p. 48). 



Fig. 1 . Basal view of the medusiform octoradial norm (seen from the subumbrella). The central sterile siphon 

 exhibits an octolobate mouth-opening, and is surrounded by a corona of sixteen reddish-yellow 

 palpons which bear numerous medusiform gonophores on their basal portion. An octoradial 

 corona of numerous tentacles, arranged in eight equidistant bunches, is placed between the 

 corona of palpons and the octolobate margin of the umbrella. Each tentacle bears three longitudinal 

 rows of tentilla, or of pedunculate cnidospheres, two paired lateral and one inferior row. 



Fig. 2. A fertile palpon, beset in the red distal half (q) with eight longitudinal rows of cnidonodes (/.;), in the 

 yellow proximal half with clusters of medusiform gonophores (Discomitrae, g). 



Fig. 3. The octolobate mouth of the large central siphon ; its labial margin is armed with a series of cnido- 

 nodes. 



Fig. 4. A group of tentacles (three larger and four smaller) and their insertion into the subumbrella. 



Fig. 5. A single tentacle, with its three rows of tentilla (an odd inferior and two paired lateral rows). 



Fig. 6. A single tentillum. d, Axial column composed of large discoidal entoderm-cells ; e, exodermal 

 epithelium ; z, fulcrum between them ; k, terminal cnidosphere. 



Fig. 7. Apical view of a Discomitra (or a medusiform gonophore). u, Exumbrella ; w, subumbrella ; cr, four 

 crossed radial canals. 



Fig. 8. Lateral view of the same Discomitra, in profile, cr, The four radial canals ; ec, ring-canal of the 

 umbrella margin. 



Fig. 9. Apical view of a young Discmtula (octoradial medusiform larva of Discoiialia). The pneumatocyst 

 (yellow) appears through the central portion of the (blue) exumbrella. ph, Central air-chamber; 

 po, its stigma ; pq, eight radial air-chambers ; pe, their peripheral stigmata ; us, muciparous glands 

 of the umbrella-margin ; t, tentacles ; k, cnidospheres. 



Fig. 10. Basal view of a somewhat older Disconula. The octolobate mouth of the central siphon and the 

 corona of eight (red) incipient palpons are visible in the centre of the subumbrella. Each tentacle 

 bears a terminal bunch of four tentilla (k). Characters as in fig. 9. (Compare on these larvae, 

 pp. 39, 45, 56, and Discalia, p. 46, PI. XLIX. figs. 1-6.) 



