488 Leuckart: Bericht üb. d. wissenschaftlichen Leistungen 



ging from the hydranth (Halocharis Ag.) Medusa, when fuUy deve- 

 loped, having a deep urabrella; mar.ubrium massive and destitute 

 of oral tentacles; marginal tentacles four, each with a clavate ex- 

 tremity and with an ocellus on the biilbous base; roof of umbrella- 

 cavity rising in four overarched Spaces between the roots of the ra- 

 diatiug canals. 



C. Agassizii M'Cr. 



Gymnocoryne Hincks. Hydrocaulus undeveloped. Hydrorhiza a 

 filiform stolon invested with a chitinous perisarc. Hydranths sessile 

 on the hydrorhiza, with numerous tentacles; the distal tentacles 

 disposed in a verticil round a conical hypostome, the others scatte- 

 red over the body. Gonosome not known. 



G. coronata Hincks. 



Gemmaria M'Cr. Hydrocaulus developed, invested by a peri- 

 sarc and rooted by a creeping filiform hydrorhiza. Hydranths clavi- 

 form with scattered capitate tentacles. Planoblasts from the body 

 of the hydranth. Umbrella at time of liberation deep bell-shaped: 

 manubrium moderately developed, destitute of oral tentacles or lobes ; 

 marginal tentacles two, developed from the distal extremities of two 

 opposite radiating canals, the alternate canals having each e small 

 tentacular tubercle at the corresponding point; the tentacles cora- 

 mence each with a large bulbous dilatation destitute of distiuct 

 ocellus, and are for the remainder of their course set with peduncu- 

 lated sacs filled with thread-cells; from the base of each tentacle 

 and intermediate tubercle a coecal claviform tube, filled with thread- 

 cells, extends for some distance in the walls of the umbrella, parallel 

 to the corresponding radiating canal (Zanclea M'Cr,). 



Gemmaria implexa M'Cr. (= Coryne briaraeus Allm.) 



Fam. Dicorynidae. Hydrocaulus developed, invested by a 

 perisarc. Hydranths with verticillate filiform tentacles. Gonophores 

 in the form of natatory ciliated sporosacs with two simple ciliated 

 basal tentacles. 



Dicoryne Allm. Hydrocaulus consisting of branched or simple 

 stems, which arise at intervals from a creeping filiform hydro- 

 rhiza. Hydranths fusiform with a single circlet of filiform ten- 

 tacles surrounding the base of a conical hypostome. Sporosacs 

 developed upon blastostyles, detaching themselves as natatory pla- 

 noblasts, ciliated over their entire surface and having two filiform 

 tentacles diverging from the proximal eod. 



Dicoryne conferta Alder. (= D. stricta Allm.) 



Fam. Bimeridae. Hydrocaulus developed and invested with 

 a perisarc, or rudimental. Hydranths with the hypostome not 

 abruptly differenciated ; tentacles filiform in a verticil round the 

 base of the hypostome. Gonophores in the form of fixed sporosacs. 



