new Genus q/* Stylasteridge. 213 



The new genus is allied to Errina, but differs from the 

 latter in the regular arrangement of the pores, as indicated 

 above. 



In Phalangopora the separation of the gastropore and 

 dactylopore systems is a further distinctive feature. For 

 although in DisticJwpora there is a series of pores on each 

 side of the branches, each series consisting of a central row 

 of gastropores and two lateral rows of dactjlopores, the differ- 

 entiation of the two systems is not so marked as in Phalan- 

 gopora^ and there are no pores on the anterior and posterior 

 surfaces. 



The specimen is small, measuring 2 inches in height and 

 3 inches in breadth across the broadest part. Colour white, 

 ccenosteura dense. The number of branchings is five or six ; 

 some branches are twisted on their axes. 



The mode of branching seems to be dichotomous, but shows 

 a tendency to the formation of a scorpioid cyme from the con- 

 tinual suppression of lateral branches on alternate sides. 



Owing to the manner in which the corallum increases in 

 thickness in the older branches, the dactylopores do not open 

 along the median lateral lines, as they do in the terminal ones. 

 Consequently on one surface of the flabellum the nariform 

 projections are more conspicuous than on the other, so that 

 the specimen may be said to have an anterior and posterior 

 surface, the term " anterior " being applied to the former. 

 The lateral dactylopores are contiguous in the younger 

 branches and separated in the older ; in one or two branches 

 the irregularly scattered dactylopores almost form a linear 

 series. 



Viewing the anterior and posterior surfaces of the branches 

 in profile, the scales arching over the mouths of the gastro- 

 pores appear like lines of tiles. 



On the youngest branches the scales lie strictly in the 

 middle line, each scale rising from the upper border of the 

 mouth of the preceding gastropore. In the older branches 

 the gastropores are separated by a considerable interval, and a 

 line joining them would be serpentine. 



A longitudinal section of a young branch shows the wide 

 canals of the gastropores cut across, also the long canals of 

 the dactylopores passing in obliquely towards the centre. 

 From the length of the gastro- and dactylopores the system of 

 canals in the coenosteum is not so well marked near the surface 

 as in some Stylasteridte. 



It is not evident from the section whether styles are 

 present in the gastropores or not ; but a coarse dissection, 

 in which the outer wall of the gastropores was removed down 

 to the base, failed to show any evidence of gastrostyles. 



