584 Chas. W. Hargitt. 



EXPLANATION OF PLATE. 



All figures were photographed natural size directly from nature. 



Fig. I. At I is shown the missing segment, of an otherwise normal specimen. Toward the per- 

 iphery may be seen typical anastomoses of the radial canals. 



Fig. 2. Medusa with nine rhopalia, the extra one at A occupying an adradial position, at the ter- 

 minus of an adradial canal, unusual in its terminal branching. 



Fig. 3. Medusa with ten rhopalia, the two extra ones occupying the same perradial segment, at P. 



Fig. 4. Medusa with only seven rhopalia, one at A being at the terminus of the much curved 

 adradial canal. At P is shown, at the margin of a complex perradial segment, a very small rhopa- 

 lium. The interradial rhopalium is lacking in the adjacent segment to the left. 



Fig. 5. Medusa having but three oral lobes, which were excised before the photograph was made, 

 two of the gonads much smaller, and the umbrella of that side also appreciably narrower. 



Fig. 6. Hexamerous medusae, having eleven rhopalia, the twelfth at P with the entire perradial 

 system of that segment lacking. On the lower right-hand side may be seen the very complex anasto- 

 moses of the canal systems of that region. 



