SCYPHOZOA 173 



adhering to the blades of Zoster a or Laminaria. It has a narrow stem 

 arising from its exumbrellar surface, by which it attaches itself 

 temporarily to seaweed. The edge of the bell is divided into eight 



Fig. 130. Longitudinal sections through A, Lucernaria and B, a strobilizing 

 scyphistoma of Chrysaora. In A the section passes through an interradius, on 

 the left on the exact line of the mesentery so as to show the subumbral pit 

 and on the right to one side so as to show the face of the mesentery. In B only 

 the right side of the section passes through an interradius. C, Transverse 

 section through Lucernaria along the line x x in A. D, Ephyra larva of 

 Aurelia. can.c. circular canal ; g. gonad ; g.f. gastral filament ; e.s. exumbrellar 

 stalk ; 7nes. mesentery ; ni.L' longitudinal muscle of mesentery ; su.p. subumbral 

 pit; ten.s. tentacle becoming later a tentaculocyst ; I.R. interradius; P.R, per- 

 radius; A.R. adradius with first indication of canal. A and C, altered from 

 Bourne; B, after Heric; D, original. 



lobes, on each of which are several short tentacles and the adhesive 

 organs which are called marginal anchors} There is no velum and 

 tentaculocysts are absent. The manubrium is well developed and the 



^ Absent in Lucernaria. 



