Genera Axinella, Phakellia, Acanthella a. o. 315 
Axinella is very variable. Roughly spoken we find branched or un- 
branched eylindrical forms and broadly expanded flabellate forms. 
In the “species” verrucosa and polypoides we have examples of the 
former extreme; in the “species” cinnamomea or damicornis an example 
of the latter. What is stated above with respect to the supposed 
resemblanc or identity of Azxöinella with Raspailia of course only holds 
true for the cylindrical forms. The flabellate forms, as we saw 
before, are often confused with. Phakellia. I refer to what I said 
about this on the first page. But I hope to have shown that flabellate 
Azinellae are different in structure from Phakellia. In Axinella the 
axis is composed of a network of funieuli; in Phakellia the network 
is formed by anastomosing funes, which are in their turn composed 
of a network of funiculi. The meshes of the axis in the former are 
bordered by funieuli, in the latter by funes; in accordance herewith 
is the fact, that on the whole these meshes of Axinella are con- 
siderably smaller than in the latter: hardly distinguishable to the 
naked eye in the former, clearly conspicuous in the latter. 
According to Rınrey (1884, p. 619) there is a sponge, called by 
him Azönella proliferans, which partly resembles Azinella, partly 
Acanthella. We have seen, however, that in the typical specimens 
of the latter genus no distinction can be made between an axial and 
an extra-axial skeleton, so distinetly seen in Azinella. As far as it is 
possible to form a clear conception of the true arrangement of the 
spicules without any illustration, I should rather not include Rıprey’s 
sponge in Azinella. 1 feel inclined to believe that the arrangement 
is more like Phacanthina, with which the external appearance is in 
perfect accordance. This can, however, only been settled by making 
a preparation of the skeleton of one of the specimens Rıprey alludes 
to.) If there is really no distinetion to be made between an axial 
and an extra-axial part, the sponge cannot, according to my views, 
be placed under Azinella. 
For similar reasons I doubt whether Dexpy (1905, p. 194) is 
richt, where he considers Acanthella flabelliformis KeuL. as a 
“connecting link between the genera Acanthella and Phakellid”. Here 
acain the skeleton has to be studied more carefully. 
Schmipr mentioned (1880. p. 282) Phakellia plicata and Ph. incisa 
—- mere nomina nuda — stating that he left them in the Zoological 
Station at Baier In my list of the sponges, which I examined in 
Ey See for the methods at the end of this article. 
