Pylonibilduiigen bei Radiolarien and Protisten iiberhaupt. 115 



bears therefore to it the same relation as in the Porodiseida 

 Ommatodiscus does to Porodiscus. This peculiar osculum is also 



here surrounded by a corona of spines, There are only 



two species of Discopyle observed, which represent perhaps better 

 two different genera; in ohne species the disk is circular, in the 

 other elliptical. In this latter the osculum lies on one pole of 

 the main axis. 



1. Discopyle osculata, Haeckel (Report, Plate 48, fig. 19). 



Disk circular , with spiny margin , three times as broad as 

 the triangular, triopyle-shaped medullary shell. Three gates of 

 the cortical shell kidney-shaped, on the inside with an interradial 

 spine, twice as broad as the three pentagonal arms. Chambered 

 equatorial girdle with twenty-four subregular chambers, in the 

 radius of one odd gate with a large marginal osculum, which is 

 as broad as the medullary shell, and surrounded by a dense corona 

 of twenty to thirty strong conical spines. 



Dimensions. — Diameter of the disk 0,15; of the cortical 

 shell 0,1 ; of the medullary shell 0,05 ; of the marginal osculum 

 0,06. 



Habitat. — Central Pacific, Station 272, depth 2600 fathoms. 



2. Discopyle elliptica, Haeckel (Report, Plate 48, fig. 20). 



Disk elliptical, four-fifths as broad as long, with spiny margin, 

 three times as broad as the triangular, triopyle-shaped medullary 

 shell. Three gates of the cortical shell roundish, on the inside 

 with an interradial spine, little broader than the quadrangular 

 arms. Chambered equatorial girdle with twenty to thirty irregular 

 chambers, on one pole of the main axis with a large marginal 

 osculum, which is one-third as broad as the length of the main 

 axis, and armed with a corona of twenty to thirty short conical 

 spines. The osculum does not correspond to a certain radius. 



Dimensions. — Diameter of the disk 0,15; of the cortical 

 shell 0,08 ; of the medullary shell 0,04 ; of the marginal osculum 

 0,05. 



Habitat. — Central Pacific, Station 267, depth 2700 fathoms. 



Ich komme nun zur Beschreibung der mit einem Pylom ver- 

 sehenen Spongodisciden. W ah rend bisher aus dieser Gruppe der 

 Radiolarien keine pylomatischen Formen bekannt waren 1 )? kann 



1) Uber Stohe's Spongotrouhus craticulatus vtrgleiche Spongopyle 

 craticulata und den 5. Abschnitt. 



I* 



