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



Distrihution. Abington, Lanarkshire ; Broughton, Hartree 

 Hill, Kilbucho, Peeblesshire ; Moorfoots, Edinburghshire. 



Sphcerozoum patulum ^ sp. n. 

 (PI. IV. fig. 12 ; woodcut, g, L) 



The spicules included under this term are geminate and 

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

 from both ends of whicli two simple, subcjlindrical, divergent 

 rays are given off, approximately in the same plane (Ph IV. 

 fig. 12 ; woodcut, g). 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. 



.Distribution. Broughton, Hartree Hill, Peeblesshire. 



Subclass NASSELLARIA, Ehrenberg. 

 Order PLECTELLARIA, H^ckel. 

 Suborder Plectoidea, Hseckel. 



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 Ha3ckel ; 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 

 j)lane and one above and the other below this plane. On two 

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

 entire, are "15 millim. in length. In another specimen (wood- 

 cut, k) there are five basal rays, with a stout ray rising i'rom 

 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. xcvii.). In the third specimen 

 (woodcut, /), which is of unusual size, there are four basal 

 rays radiating from a centre, from which also an upriglit ray 

 sjj-uiigs. The rays are cylindrical and smooth and bifurcate, 



* ' Clialleuger ' Rt'port, pt. i. pp. 40-4-5, pi. iv. 



