84 JOHNS HOPKINS UNIVERSITY MORPHOLOGICAL MONOGRAPHS. 



The mass with darkly stained granules is the remains of a thread cell. The 

 ectoderm and a small part of the supporting lamella only are figured. Note the 

 large ganglion cell. X920. pp. 74, 75. 



Fig. 29. Part of a transverse section of a tentacle of Tripedalia. The endoderm 

 is not figured. The supporting lamella is seen to be considerably thinner than in 

 Charybdea. Note the subectodermal muscles, as also the muscle fibers to the thread 

 cells. X920. pp. 69, 74, 75. 



Fig. 30. This is a transverse section through the endothelium of a tentacle of 

 Charybdea in the line c d of Fig. 32. The dark lines bounding the polygonal areas 

 are the thickenings of the sides of the walls of the cells in the line indicated. The 

 central dots are the centrad continuations of the flagella. X920. p. 76. 



Fig. 31. This figure is a transverse section through a tentacle of Charybdea at 

 about the middle of Fig. 32, i. e. so near to where the tentacle joins the pedalium, 

 that the muscles within the lamella have all come to lie under the ectoderm. The 

 ectoderm is not shown. X920. pp. 75, 70. 



Fig. 32 A longitudinal section through the supporting lamella only, of a 

 tentacle of Charybdea, is here shown. In the upper part of the figure the muscle 

 fibers are seen wholly enclosed by the supporting lamella. In the middle of the figure 

 they are seen to pass out of their canal. In the lower part of the figure, the support- 

 ing lamella is seen to bend to the right where it becomes continuous with the lamella 

 of the pedalium. X920. p. 75. 



