in d. Naturgesch. d. nied. Thiere währ. d. Jahre 1872—1875. 437 



developed hydrocaulus and a creeping filiform hydrorhiza; the whole 

 invested by a distinct perisarc. Hydranths fusiform, with scattered 

 filiform tentacles. Planoblasts borne on the hydrocaulus. Form of 

 raedusa unknown. 



C. parasiticum Cav. 



Fam, Corynidae. Hydrocaulus developed. Hydranths with 

 scattered or more or less spirally capitate tentacles. Gonophores 

 fixed sporosacs. 



Coryne Gärtn. Hydrophyton consisting of a simple or branched 

 hydrocaulus, rooted by a creeping filiform hydrorhiza; the whole 

 invested by a chitinous perisarc. Hydranths claviform, with scatte- 

 red capitate tentacles. Sporosacs developed from the body of the 

 hydranth. 



C. pusilla Gärtn. (= C, glandulosa Lara.), C. vermicularia 

 Hincks, C. vaginata Hincks, C. fruticosa Hincks, C. ramosa Sars, 

 caespes n. sp. la Spezziä. Zweifelhaft: C. nutans n, sp. Schottland. 



Actinog onium n. gen. Hydrophyton consisting of a deve- 

 loped hydrocaulus springing from a creeping filiform hydrorhiza, 

 the whole invested by a conspicuous perisarc. Hj^dranths claviform, 

 with scattered capitate tentacles. Sporosacs developed from the body 

 of the hydranth and giving origin to actinulae. 



A. pusillum van Ben. (= Coryne van ßenedini Hincks). 



Fam. Syncoryuidae. Hydrocaulus developed or not deve- 

 loped; hydranthus with scattered or partly scattered and partly 

 verticillate capitate tentacles. Gonophores in the form of medusi- 

 form planoblasts with four radiating canals and simple (rarely un- 

 developed) marginal tentacles. 



Syncoryne Ehrbg. Hydrophyton consisting of a simple or bran- 

 ched hydrocaulus, with creeping filiform hydrorhiza ; the whole in- 

 vested by a chitinous perisarc. Hydranths claviform, with scattered 

 capitate tentacles. Planoblasts developed upon the body of the hy- 

 dranth. Medusa, at the time of liberation, with a deep bell-shaped 

 umbrella; manubrium raoderately large, destitute of oral tentacles; 

 marginal tentacles four, with bulbous bases usually furnished with 

 on ocellus; or the medusae may never bocome free, the marginal ten- 

 tacles remaining at the same time in an imperfectly developed State. 



S. Sarsii Lov., L. Loveni Sars (= racemosa Lov.), S. gravata 

 Wright, S. mirabilis Ag., S. pulchella AUm., S. decipiens Duj. (mit 

 Stenyo Duj.), Ä. frutescetis n. sp. Dublin, S. eximia Allm. (= Cor. 

 Listeri Alder), S. ferox Wriglit, S. reticulata A. Ag. Zweifelhaft; 

 S. Listeri van Bened., S. Johnstoni van Ben,, S. Lovenii van Ben., 

 S. rosaria A. Ag. 



Corynitis M'Cr. Hydrocaulus absent, so that the hydranths are 

 sessile on the hydrorhiza. Hydranths cylindroid. Planoblasts sprin- 



