BRANCHIOCERIANTHUS IMPERATOR (ALL:\rAN). 261 



Hamann, 0. 



'82. Der Organismus der Hydro id-Polypen. Jen. Zeit. Bd. 8. 

 Vol. 8. {Jena). 

 HiNCKS, Th. 



' 68. British Hjdroid Zoophytes. 1868. 

 Von Koch, G. 



' 73. Vorläufige Mittheiking über Cölenteraten. Jen. Zeit. Bd. 7. 

 Mark, E. L. 



' 98. Preliminary report on Branchiocerianihus urceolus. Bidl. of 



the Mus. of Comp. ZooJ. Vol. XXXII. No. 8. 

 * 99. " BrancMoceriantJms," a correction. ZooL Anz. Bd. XXII 

 No. 590. 

 Weismann, A. 



'83. Die Entstehung der Sexualzellen bei den Hydromedusen, 1883. 



Explanation of Plate. 

 PI. XIV. 



The hydranth with the upper half and the lowest part of the hydro- 

 caulus. Nat. size. 



PI. XV. 



Reference letters : B. hypostomal region of the disc ; Ect. ectoderm ; End. 

 endoderm ; iZ upper, H' lower, cavity of the hydranth ; ic. intercalated cord ; 

 ones, mesoderm ; mi. marginal tentacle ; p. peduncle of the gonosome ; R. 

 outer region of the disc, provided with the radial canals ; re. radial canals ; 

 t.h. lumen of the base of the marginal tentacle. 



Fig, 1. Surface-view of a portion of the disc with gonosomes (p) and 

 marginal tentacles {nit.). Nat. size. 



a upper wall of the disc, h a part of the diaphragm in the hydranth. 



Fig. 2. Longitudinal section through the outermost margin of the disc 

 Zeiss a X 4. 



