726 Leuckart: Bericht üb. d. wissenschaftlichen Leistungen 



Sporadopora gen. n. (Zuerst Polypora benannt , mit 

 einem bereits anderweit vergebenen Namen.) CoralUim pure white, 

 coraposed of finely reticular, but compact coenenchym, forming stout 

 vertical stems usually compressed from before backwards , so as to 

 be oval in transverse section. Stern giving ofif a limited number of 

 irregularly dichotomous branches, which are flattened like it and 

 tend to coalesce by their lateral margins and assume a flabcllate 

 form, which is sometimes somewhat curved. Surface of the coral- 

 lum smooth and entirely even. Peres of both kinds with simple 

 circular mouths; irregularly scattered. Gastropores larger, less nu- 

 merous, with a deeply seated brush-like style and very thin and 

 delicate tabulae placed at irregulär intervals, Dactylopores devoid 

 of a style. Ampullae, in male Stocks, ovoid, entirely immersed 

 beneath the surface of the corallum. Peres and ampullae more 

 abundant on one face of the flabellum, than on the other. Gastro- 

 zooids cylindrical, with four club-shaped tentacles, dividing at their 

 bases into four main canals. Dactylozooids of various sizes, retracted 

 entirely within the pores when at rest. Gonophores in male 

 Stocks ovoid, with a club-shaped spadix ; one, two or three present 

 in each gonangium , attached directy to offsets of the coenosarcal 

 canals. Female Stocks unknown. Sp. dichotoma n. sp. Rio de la Plata. 



Pliobothrus Pourt. Corallum branching with a tendency to 

 form a flabellum. Surface smooth, marked with small linear openings 

 arranged in rows, which in the recent state contain branches of the 

 superficial coenosarcal meshwork. Inner parts of the corallum very 

 coarsely porous. Pores irregularly scattered. Gastropores circular 

 mouthed, their cavity tubulär above, but expanding below into a 

 basin-shaped Chamber, without a style, often with one or two ta- 

 bulae. Dactylopores showing as minute openings at the tips of 

 small tubulär projections, devoid of styles. Ampullae rounded cavi- 

 ties; in the female very large, in the male smaller; placed deeply, 

 often in the axis of the corallum. Gastrozooids flask-sliaped, devoid 

 of tentacles, communicating with the coenosarcal meshwork by 

 nuraerous offsets arising all around their bases. Dactylozooids enti- 

 rely retracted when at rest. In the female a single gonophore in 

 each gonangium; in the male a group of gonophores (?) in each am- 

 pulla. 



Errina Gray. Corallum branching with a tendency to form 

 an irregulär flabellate expansion. Pores most abundant at the tips 

 of the branches; irregularly scattered. Dactylopores with delicate 

 nariform or scale-like projections, which vary mucli in form, being 

 sometimes drawn into tubes opening on one side by a slit as the 

 pore-mouth, but often coalescing, so that two or three projections 

 have a common base and form long scales perforated by the pores ; 

 devoit of styles; scales all with a tendency to incline towards the 



