REPOHT ON THE TETRACTINELLIDA, 
413 
stelligerus, Carter^; Vioa johnstoni, 0. Schmidt,^ and several new species to be 
described later. 
The list of astrophorous Monaxons not directly related to Tethya is sufficient to 
show that the astrophorous character is by no means so very exceptional in the 
Monaxonid group. A feature which to my mind is more suggestive of affinity to the 
Stellettidse is the association of one or more very small asters with the spheraster, one 
of these smaller forms being sometimes a chiaster with terminally tylote actines, of 
essentially the same characters as the chiaster of species of Myriaster and Anthastra, 
this suspicion of alliance suggested by the association of two asters, one of them a 
chiaster, is, however, weakened by the fact that the chiaster is a very simple and 
apparently somewhat primitive form of spicule and might very well be independently 
evolved in widely different sponges. 
The existence of a considerable number of astrophorous Monaxonida requires to be 
recognised in classification, a task which is much facilitated by the excellent arrangement 
of the Monaxonid sponges proposed by Messrs. Ridley and Dendy ; into this I shall 
introduce as few changes as possible. 
Putting on one side the Homoraphidse, it will be observed that the Monaxonida 
of Ridley and Dendy fall readily into two groups, those distinguished by the presence 
of sigmaspires, sigmas, or chelae, and those in which the microsclere when present is 
some form of aster, it may be a euaster, or a spiraster, or some closely related form. 
I propose, therefore, to recognise these two groups as suborders, the former as the 
Meniscophora, the latter as the Spintharophora.^ The Meniscophora will include the 
family Heteroraphidse, Ridley and Dendy, and the Desmacidonidse, 0. Schmidt ; the 
Spintharophora, the Axinellidse, Suberitidae, Spirastrellidae, and Tethyidse, and such 
other aster-bearing sponges as will be described and discussed later. The Homoraphidae, 
since they are without the guiding microsclere, will be relegated to a third suborder, 
the Asemophora. 
It will probably be objected that the Spintharophora include many sponges, 
and even a whole group of sponges (Suberitidae), which are totally devoid of micro- 
scleres ; to this it may be replied that the alliance of these sponges without 
microscleres to those with which they are associated, is discoverable on other grounds, 
and that once united to aster -bearing sponges, a group arises to which a name may be 
given as generally characteristic without being necessarily applicable to every constituent 
individual, for a name cannot always contain in itself a definition. Further, we have 
already seen that the absence of a microsclere is a matter of less importance than its 
character when present [vide Introduction), hence when in a natural group of sponges 
microscleres are generally absent, it becomes a matter of great interest to discover cases in 
* Ann. and Mag. Nat, Hist., ser. 5, vol. vi. p. 124. 
* (^yivKKos, 0 , a lunula ; 6, a sparkle. 
“ Loc. cit., p. 78, pi. vii. fig. 17. 
