125 



developed hydrocaulus aud a creeping filiform hydrorhiza; the whole 

 invested by a distinct perisarc. Hydranths fnsiform, with scattered 

 filiform tentacleR. Planoblasts borne on the hydrocaulus. Form of 

 raedusa unknown. 



C. parasiticum Cav. 



Fam. Corynldae Hydrocaulus developed. Hydranths with 

 scattered or more or less spirally capitata teiitacles. Gonophores 

 fixed sporosacs. 



Coryne Gärtn. Hydrophyton consistiug of a simple or branched 

 hydrocaulus, rooted by a creeping filiform hydrorhiza; the whole 

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

 red capitata tentacles. Sporosacs developed from the body of the 

 hydrauth. 



C. pusilla Gärtn. (= C. glandulosa Lam.), C. vermicularis 

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

 caespes n. sp. la Spezzia. Zweifelhaft: C. nutans n. sp. Schottland. 



Actinogonium n. gen. Hydrophyton consisting of a deve- 

 loped hydrocaulus spriuging from a creeping filiform hydrorhiza, 

 the whole invested by a conspicuous perisarc. Hydranths 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. Syncorynidae. 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, wit^j scattered 

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

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

 umbrella; manubrium moderately 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., fj. Loveni Sars (= racemosa Lov.), S. gravata 

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

 Stenyo Duj.), /S. frutescens n. sp. Dublin, S. eximia Allm. (= Cor. 

 Listeri Alder), S. ferox Wright, S. i'eticulata A. Ag. Zweifelhaft; 

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

 S. rosaria A. Ag. 



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

 sessile on the hydrorhiza. Hydranths cylindroid. Planoblasts sprin- 



