REPORT ON THE RADIOLARIA. 1739 



1. Ccelodasea ramosissima, Haeckel. 



Ccelodendrum ramosissimum (partim), Haeckel, 1862, Monogr. d. Radio!., p. 363, Taf. xiii. fig. 4. 



Spongy framework of the spherical bivalved mantle very dense and thick, produced by very 

 numerous, irregular anastomoses of the lateral and terminal branches, which arise from the hollow 

 tubes. The last and thinnest terminal branches are forked, as seen in the radial section of fig. 4 

 (loc. tit.), their ends are closed and armed with some very small denticles (not open, as figured in 

 fig. 4). In my Monograph I had confounded this species with Ccelodendrum ramosissimum, which 

 however, may possibly be its ancestral form. 



Dimensions. Diameter of the spongy spherical mantle 2 to 2'5, of the central valves 0'15. 



Habitat Mediterranean (Messina), surface. 



2. Ccelodasea spongiosa, n. sp. 



Spongy framework of the bivalved mantle rather loose, not nearly so thick and dense as in the 

 preceding species. The last and thinnest terminal branches are prolonged into denticulate, zig- 

 zagged, radial filaments, which bear at their distal end an anchor with two recurved teeth (similar 

 to Ccelodrymus ancoratus, PI. 121, figs. 9, 10). 



Dimensions. Diameter of the spongy spherical mantle 3 to 3'2, of the central valves 0'24. 



Habitat. Equatorial Atlantic, Station 347, depth 2250 fathoms. 



Family LXXXV. COSLOGRAPHIDA, n. fam. (Pis. 122, 126-128). 



Definition. PH^EODARIA with a bivalved lattice-shell, composed of two hemispherical 

 valves, a dorsal and a ventral. A conical cupola or a helmet-shaped galea arises on the 

 apical pole of each valve, therefore on the opposite poles of the sagittal axis. The cavity 

 of the galea communicates with the sagittal rhinocanna, a peculiar nasal tube, which rests 

 upon the valve, and is connected with the galea by a simple or double frenulum ; its 

 opening being directed towards the proboscis. Three or more branched hollow radial 

 tubes arise from each valve, and are symmetrically disposed. Sometimes their branches 

 form an outer bivalved mantle. The central capsule is so enclosed between the two 

 inner valves, that its three openings lie in the open frontal fissure between them. 



The family Ccelographida, the last family of the PILEODAKIA, exhibits the highest 

 degree of morphological development, not only in this group, but among all Radiolaria. 

 They attain also the greatest size of all members of the class, since the diameter of their 

 body is sometimes more than 20 mm., and in a few species even more than 30 mm. 

 The complexity of their structure attains at the same time such a high degree, that 

 they may be regarded as the most complicated, and (in a morphological sense) as the most 

 highly developed of all Protozoa. Nevertheless their body always remains a single cell, 



