58 Dr. G. J. Ilinde on Radiolaria from the 



Distribution. Abington, Lanarkshire ; Broughton, Hartree 

 Hill, Kilbucho, Peeblesshire ; Moorfoots, Edinburghshire. 



Sphrnrozoum patulum, sp. n. 

 (PI. IV. fig. 12 ; woodcut, r/, h.) 



The spicules included under this term are geminate and 

 cruciform. In the geminate forms there is a short central rod, 

 from both ends of which two simple, subcylindrical, divergent 

 rays arc given off, approximately in the same plane (PI. IV. 

 fig. 12 ; woodcut, y). The rays are similar in the cruciform 

 spicules, but the median rod is reduced to a slight central 

 expansion (woodcut, h). Both kinds of spicules are present 

 in recent species of the genus *, and they have been likewise 

 noted from Jurassic strata. The geminate spicules differ from 

 any known kind of sponge-spicules. 



The central rod of these spicules is from "Olo to '03 millim. 

 in length, and the rays are from '03 to "13 millim. in length. 



Dititribution. Brougiiton, Ilartree Hill, Peeblesshire. 



Subclass NASSELLARIA, Elirenberg. 

 Order PLECTELLARIA, Hteckel. 

 Suborder Plectoidea, Haeckel. 



Nassellaria with a rudimentary, originally tripodal, skele- 

 ton, composed of radial spines arising from one common 

 central point or central rod. (Chall. Rep. pt. ii. p. 898.) 



There are a few forms in the chert which appear to belong 

 to the above suborder, but they cannot be included in any of 

 the known genera referred thereto by Ilajckel ; and it seems 

 undesirable, since the specimens are rare and not perfect, to 

 propose three new genera for them. In one specimen (wood- 

 cut, *) there are five straight, nearly cylindrical rays proceeding 

 from a minute rounded centre ; three of the rays are in one 

 ])lane and one above and tlie other below this plane. On two 

 of the rays are small .opines or processes. The rays, when 

 entire, are T5 millim. in length. In another specimen (wood- 

 cut, k) there are five basal rays, with a stout ray rising from 

 the centre. The rays are spinous, and there are traces of 

 irregular tissue connecting them, as in the recent Plectanida 

 (Chall. Rep. pt. ii. p. 919, pi. xevii.). In the third speeinieu 

 (woodcut, ?), whicii is of unusual size, there are four basal 

 rays radiating from a centre, from whicii also an upright ray 

 s])nngs. The rays are cylindrical and smooth and bifurcate, 



* ' ChalleugiT ' lu'port, j.t. i. pp. 40-45, pi. iv. 



