'o- 



PLATE XLV. 



Poiyita fungia, n. sp. (p. 67). 



Fig. 1. Vertical meridional section through the corm. p, Pneumatocyst ; ph, its central chamber; pk, con- 

 centric ring-chamhers ; p 1 , tubercles of the upper surface ; j' 2 , thickened chitinous layers of the 

 upper wall ; p*, septa between the ring-chambers ; p*, under surface of a high radial fold ; 

 pe, stigmata ; uh, hepatic vessels of the centradenia ; un, its renal vessels ; uu, limbus umbrella? ; 

 /, tentacles ; gs, gonostyles ; so, their mouth ; g, gonophores ; st, tabula gastrobasahs ; sm, stomach 

 of the central siphon ; sf, its basal fissures (ostia of the radial canals) ; xr, proboscis ; ss, mouth. 



Fig. 2. A portion of the exumbrella ; highly magnified, ue, The radial folds ; ce, pallial canals ; pa, radial 

 rows of stigmata. 



Fig. 3. Basal view of the centradenia, isolated by maceration, un, The white annular kidney ; sh, the brown 

 liver ; si, central star composed of hepatic vessels ; sx, basal insertions of the sexudl siphons ; 

 cr, radial canals. 



Fi". 4. Basal view of the central siphon, the walls of which are highly contracted and the octolobate mouth 

 widely opened. In the fundus of the stomach are visible eight pairs of fissures (sf), the gastral 

 openings of sixteen radial canals, sm, Radial folds ; si, thickened labial margin of the mouth. 



Fig. 5. A radial segment of the pneumatocyst ( pf) of another Porpita (timbclla). The upper surface of the 

 float exhibits numerous radial rows of stigmata (2>e) in the back of prominent ridges, pk, Con- 

 centric ring-chambers ; ph, central chamber. 



Fig. 6. A small portion of the centradenia in horizontal section ; highly magnified, sa, Central siphon ; 

 sw, radial folds of its inside ; d, entoderm ; e, exoderm ; in, muscles ; st, lamina gastrobasahs ; 

 pt, trachea? ; kb, cnidoblasts ; ka, auroblasts (air-secreting cells). 



Fi". 7. A small portion of the kidney (un), in horizontal section ; highly magnified. Characters 3S in fig. G. 

 cm, Hepatic vessels. 



Fig. 8. A small portion of the kidney (un) and a sexual siphon (sx) in vertical section. Characters as in 

 figs. 6, 7. e 1 , Exoderm of the subumbrella; e 2 , inner apophyses of it, piercing the fulcrum (z); 

 e 3 , air-secreting exoderm. Some trachea? (jrt) pierce the fulcrum and pass into the exoderm of the 

 sexual siphon (sx). 



