REPORT OX THE RADIOLARIA. 1521 



Legion IV. PH^EODARIA, 

 vel Cannopylea, vel Pansolenia (Pis. 99-128). 



Phceodaria, Haeckel, 1879. 

 Tripylea, Hertwig, 1879. 

 Cannopylm, Haeckel, 1881. 

 Pansolenia, Haeckel, 1878. 



Definition. Radiolaria with a double membrane surrounding the central capsule, 

 which bears on one pole of the main axis a peculiar astropyle, or a tubular main-opening, 

 in the centre of a circular radiate operculum. Usually (but not constantly) a pair of 

 small, lateral, accessory openings (or parapylse) on the opposite pole of the main axis. 

 Extracapsulum constantly with a phseodium, or with a voluminous aggregation of peculiar 

 dark pigment bodies (phseodella) covering the astropyle of the central capsule. Skeleton 

 siliceous or silicated, always extracapsular, very rarely wanting. Fundamental form 

 very variable, originally monaxon, often dipleuric or bilateral. 



The legion PH.EODARIA, or CANNOPYLEA, in the extent here defined, was constituted 

 by me in 1878, in my Protistenreich (p. 102) under the name PANSOLENIA. This 

 name was given on the supposition that the skeleton of these interesting Radiolaria is 

 always composed of hollow tubules, in contrast to that of the other Radiolaria, where it is 

 never tubular. But I was soon convinced that this supposition was erroneous, that in a 

 great part of the PANSOLENIA the skeleton is not composed of hollow tubules but of 

 solid bars, and that a constant, very characteristic, and never failing mark of this group 

 is to be found in the peculiar phseodium, a voluminous, constant, extracapsular pigment 

 body. Therefore, in 1879, I changed the name into PHCEODARIA, and having discovered 

 in the collection of the Challenger an astonishing number of new and wonderful types 

 of this group, I described, in a preliminary note on it, four different orders and ten families 

 with thirty-eight genera (Ueber die Phseodarien, eine neue Gruppe kieselschaliger mariner 

 Rhizopoden ; in Sitzungsberichte der Jenaischen Gesellschaft fur Medicin and Natur- 

 wissenschaft. Sitzung vom, 12th December 1879). 



In the same year (1879), Richard Hertwig, in his excellent work entitled Der Organ- 

 ismus der Radiolarien, published the first accurate description of the intimate structure 

 of the soft body of the PANSOLENIA, and mainly of their central capsule ; and having 

 always observed, in the few representatives examined by him, three openings in 

 the capsule (one main-opening and two accessory openings), he called them TRIPYLEA 

 (loc. cit. p. 87), being guided by the erroneous supposition that these three openings are 



(ZOOL. CHALL. EXP. PART XL. 1886.) Rr 191 



