34 liElTISH rEESHWATEB HELIOZOA. 



R. intermedia Penard. — Spicules short, elliptical in broud 

 view -with curved ends in narrow view, not numerous and all 

 arranged tangentially ; pseudopodia tenuous, granuliferous. 

 Diameter 35 ;u to 40 (u. 



B. hrunii Penard. — Body small ; spicules numerous, small, 

 acicular, extending for a considerable distance along each of 

 the pseudopodia ; the pseudopodia are long, tenuous and 

 granuliferous. Diameier 12 fi to 13 fx. 



R. coerulea Penard. — Body small ; spicules not numerous,, 

 small, acicular, arranged tangentially around the body; 

 nucleus large ; contractile vesicles large, several in number ; 

 plasma bluish in colour; pseudopodia long, tenuous, granu- 

 liferous. Diameter 13 fi to 16 ju. 



R. ambigua 'Penard. — Spicules comprising three kinds of 

 thin discs, in broad view respectively oval, elongate oval and 

 fusiform, the latter extending for a considerable distance 

 along the pseudopodia ; one or more contractile vesicles. 

 Diameter of body ciO (u to 40 // ; size of spicules about 5 fi by 

 3/i, 12 ;u by 3 ju and 20 (u by 2 (U respectively. 



R. symmetrica Penard. — Spicules comprising two kinds of 

 thin discs, in broad view elliptical, one kind being about 10 /^ 

 in length, the other 8 fi, both about 2'5 /xin width and slightly 

 curved in narrow side view, the larger of these forming 

 tubular-shaped investments around the pseudopodia for the 

 major portion of their length. Contractile vesicles one or 

 more; pseudopodia tenuous, granuliferous. Diameter of body 

 20 ju to 25 /x or sometimes more ; diameter over spicular 

 investment up to 64 ju. 



Synopsis op British Species. 



Spicules spindle-shaped with flattened points; usually in 

 colonies; diameter of body about 80 /x. (1) R. viridis. 



Spicules disc-shaped; usually iu colonies ; diameter of body 

 about 30 ju. (2) R. elegans. 



Spicules spindle-shaped, with acicular points; usually 

 solitary; diameter of body about 55 ^u. (3) U. pallida. 



1. Raphidiophrys viridis Archer. 

 (Plate LXIX, fig 2 ; PI. LXX, fig. 2.) 



Raphidiophrys viridis 

 Abchbb Qrt. Jrn. Micr. Sol. (n.s.) VII, 1867, p. 179; op. cit. IX, 

 1869, p. 255, pi. xvi, f. 2. 



