298 



NATURE 



[yan. 24, 18S4 



specific forms of all Nassellaria [Cystocorida, Cystopilida, Cysto- 

 phoiinida, Cyslocapsida, CystoperiJa, Cyslophatuida, "Prodrom.," 

 1881, p. 426). 

 ~^ 4. Order IV. Ph^odaria, Hkl., 1879 (= PansoUnia, 

 Hkl., 1878 = Tripylca, Hertwig, 1879). 



Central capsule always uniaxial, sometimes almost spherical, 

 sometimes lenticular or oval, always w ith two different poles of 

 the axis. At one pole invariably the characteristic principal 

 opening witli radiated operculum, from which the bush of pseudo- 

 podia project through a tube ; at the other pole, frequently (though 

 not invariably) ti\o or more accessory openings. Nucleus 

 usually only late divided into numerous small nuclei. Capsule 

 membrane double. Extracapsularium usually (or always '/) with 

 zooxanthella; distinguished by \he p/utodium, a voluminous body 

 of pigment lying excentrically in the gelatinous sheath round 

 the principal opening. Skeleton always extracapsular, consist- 

 ing of silicium or of a silicate, usually composed of hollow tubes, 

 polymorphous (wanting only in the most simple forms, Phaodina, 

 &c.). 



4A. Sub-order VII. Ph;eocystia, H1<1., 1879. Ph^^odaria, 

 without skeleton, or with a rudimentary skeleton formed merely 

 of detached siliceous tubes (or of reticulated pieces of silex) 

 scattered outside the central capsule. 



Family 21. Phreodinida, Hkl., 1879. Skeleton entirely 

 wanting [Pliaodhia, Phicodella). 



Family 22. Cannorapbida, Hkl., 1879. Skeleton consisting 

 of detached hollow tubes or reticulated pieces of silex, de- 

 posited tangentially round the central capsule (Cannoraphis, 

 Thalassoplnneta, Diclyocha). 



Family 23. Aulacanthida, Hkl., 1862. Skeleton consisting 

 of a superficial pallium of fine tangential tubes and a number of 

 strong radial spicules (simple or branched) which pierce the 

 mantle {Aulocantha, Aulospathis, Auhmpliis, Aulodendruni, 

 &c). 



4B. Sub-order VIII. Phajogromia, Hk)., 1879. Phseodaria 

 with a dipleuric single-chambered shell having a large opening, 

 usually armed with one or more teeth at the basal pole ; besides 

 the primary, often several secondary openings. 



Family 24. Lithngonida, Hkl., nov. fam., single-chambered 

 dipleuric shell, with solid wall of peculiar crystalline structure, 

 like porcelain {Lithogromia, Tuscarora). 



F.amily 25. Challengerida, John iWurray, 1876. Single cham- 

 bered shellsj varying greatly in form, with porous glass-like 

 wall, and very fine, perfectly regular, hexagon,al pores (resembling 

 the structure of diatoms) {ChalUngeria, GazelUtta, Porciipiiiia, 

 Sec). 



4c. Sub-order IX. Phseosphjeria, Hkl., 1879. Phteodaria 

 having a spherical, or subspherical, fenestrated shell, usually 

 consisting of one single, rarely of two concentric spheres ; some- 

 times with a large principal opening, sometimes without ; partly 

 with, partly without, radial spicules. Beams of the reticulum 

 sometimes solid, sometimes hollow. 



Family 26. Castanellida, Hkl., 1879. Fenestrated shell, 

 spherical, simple, composed of solid rods, having at one point a 

 large principal opening (often armed with a corona of spicules), 

 with or without radial spicules (Castanella, Castanidium, Sec). 



Family 27. Circoporida, Hkl., 1879. Fenestrated shell, spheri- 

 cal, subspherical, or polyhs-dric, composed sometimes of reticu- 

 late plates, usually with hollow, radial spicules, always with one 

 large, principal opening, and with several detached porous arese 

 (Circoporus, Porostcphanus, Porospathis, &c.). 



Family 28. Sagenida, Hkl., nov. fam. Fenestrated shell, 

 sometimes spherical, sometimes subspherical or polymorphous, 

 forming a spongiose plexus of solid beams, without principal 

 opening {.Sagcna, Sagemdium, Sic). 



Family 29. Aulospha^rida, Hkl., 1S62. Fenestrated shell, 

 spherical, more rarely subspherical or polymorphous, composed 

 iua peculiar fashion of hollow tubes, usually with hollow, radial 

 spicules, without principal opening {Aulosphara, AulopUgma, 

 &c.). 



Family 30. Cannospheerida, Hkl., 1879. Fenestrated shell, 

 spherical or subspherical, double. The inner (medullar layer) 

 composed simpily of solid beams, the outer (cortical layer) of hol- 

 low tubes with radial spicules at the nodes of junction; both 

 layers connected by hollow, radial rods {Cannosphcem, Calo- 

 cantha, Sec). 



4D. Sub-order 10. Pha;oconchia, Hkl., 1S79. Pha:odaria, 

 having a bivalve fenestrated shell, composed Uke that of a mussel, 

 of two convex, separate, perforated valves, with or without 

 hollow, radial tubes. 



Family 31. Concharida, Hkl., 1879. Fenestrated shell, with 

 out radial spicules, composed of two smooth, hemispherical or 

 lenticular valves, the edges of which usually catch one an 

 other by rows of teeth (Concharium, Conchidium, Conckopsis. 

 Sec). 



Family 32. Ccelendrida, Hkl., 1862. Fenestrated shell com 

 posed of two hemispherical or lenticular valves, having pro 

 cesses in the form of large, hollow, radial spicules, usually 

 dendritically branched at their apical, centre points or at the 

 two poles of the transverse axis of tlie shell (Ca-lodeiidrum, 

 Ccclothamna, &c.). 



Differential Characters of the Four Orders of Radiolaria 



Holotrypasta 



Radiolaria having the capsule membrane pierced on all sides. 



I. ACANTHARIA. II. SPUMELLARIA. 



Central capsule originally 



spherical. 



Homaxonous. 



Cafisule membiane pierced 

 equally everywhere by in- 

 numerable fine pores. 

 {Peripylea). 



Skeleton acanthine. 



Zooxanthellas usually (or in- 



variai ly ?) w anting. 



Without phceodium. 



Merotrypasta 

 Radiolaria having the capsule membrane partially pierced. 



Central capsule originally 



spherical, 



Homaxonotis. 



Capsule membrane pierced 

 equally everywhere by in- 

 numerable fine pores. 

 (Peripylea). 



Skeleton siliceous. 

 Zooxanthellae usually present. 



Without phffiodiuro. 



III. Nassellaria. 



Central capsule oval or 



conical. 



Monaxonous. 



Capsule membrane with a 



single area of pores at the oral 



pole of the principal axis. 



(Alonopylea). 



Skeleton siliceous. 

 Zooxanthellai' usually present. 



IV. Ph.«odaria. 



Central capsule oval or sub- 

 spherical. 

 Monaxonous. 



Capsule membrane with a 



single simple principal 



opening and often several 



accessory openings. 



(Tripylea). 



Skeleton siliceous. 

 Zooxanthellae usually (or in- 

 variably ?) wanting. 

 Always with phseodium. 



Withovit phajodium. 

 Conspectus Ordiniim et Familiarum Radiolarium classis 



Genus typicum 



I. Ordo: 

 Acantharia 

 Holotrypasta 

 skeleto acan- 



II. Ordo: 

 Spumeliaria 

 Holotrypasta 

 skeletu defi- 



cienle aut 



siliceo poly- 



morpho 



I. Acanthometra f i. 



(sinetesia) I2. 



I II. Acanthophracla ("3. 



I (testa compJeta) \ 4. 



III. CoIIodaria 

 (sine testa) 



\l 



Actinelida Actinelius 



Acanthomda Acanlhonia 



Dorataspida Dorataspis 



Diploconida Diploconus 



ThalassicoUida Actissa 



Collozoida Collozoum 



Thalassosphaerida Physeniatium 



Sphaerozoida Sphaerozoum 



IV. Sph: 



III. Ordo: , 

 Nassellaria ' V. Pie. 

 Merotrypasta [^ (sine test; 



membra 



capsula; s 



phci, sii 



phaeodi 



Tellaria 

 npleta) 



ellaria 

 corapleta 





VI. Cyrlellaria 

 (testa completa) 



IV. Ordo: 



PhKod.-iria 

 Merotrypasta 



mcmbtana 

 capsula: dup- 



plici, cum 

 phaeodio 



1=5. 



IX. Phaeospharia 



(testa globosa aut ' 



subglobosa) 



X. Phjeoconchia 

 (testa bivalva) 



Sphasrida 

 . Collosphaer 

 , Pylonida 

 , Zygartida 

 . Litheiida 

 , Discoida 



, Cystidina 

 Plectoida 

 Steph; 



, Spyroida 



, Botryoida 



. Cyrtida 



Phaeodinida 



Canr.orhaphida 



Aulacanthida 



Lithogromida 



Challengerida 



Castanellida 



Circoporida 



Sagenida 



Aulospbaerida 



Cannosphffirida 



Concharida 



Coelodendrida 



Phorraospha 



Collosphaera 



Tetrapyle 



Didyniocyrtis 



Porodiscus 



Lithelius 



Cystidium 



Plagiacantha 



Lithocircus 



Dictyospyris 



Botryocyrtis 



Diciyophimus 



Phaodina 



Thalassoplancta 



Aulacantha 



Lithogromia 



Challengeria 



Castanella 



Circoporus 



Sagena 



Aulosphaera 



Cannosphaera 



Concharium 



Coelodendrum 



