1905, | SPONGE CLATHRINA CONTORTA, 5 
was really a specimen of variabilis, while the specimen of contorta 
of which the spicules were figured (U. c. figg. 8, 9, 10) was really a 
specimen of complicate ; and that amongst nine of Bowerbank’s 
specimens examined by me I have found four distinct species 
confused together—to wit, complicata, variabilis, coriacea, and 
“ Ascetta spinosa Lendenfeld”: I think it is not necessary to say 
more in support of the statement that Bowerbank’s species 
contorta was of absolutely no systematic value whatever, but 
represented merely an ill-defined jumble of different species. 
In 1872 Haeckel, in his ‘ Kalkschwiimme’ [2], used Bowerbank’s 
specific name contorta for a sponge which he described in detail. 
Haeckel pointed out quite rightly that the external characters of 
contorta as set forth by Bowerbank were no guide whatever to its’ 
identification, since a quite similar mode of growth characterises 
other Ascons. Haeckel therefore diagnosed contoria by details of 
its spiculation. The diagnosis given is incorrect in two points, 
namely, in stating that “the monaxons possess a lance-head at 
their distal extremity, and that the gastral rays of the quadri- 
radiates are “curved oralwards”; two statements that lead me to 
suspect that Haeckel’s material of contorta was, like Bowerbank’s, 
contaminated by admixture of Lewcosolenia complicata. Haeckel, in 
his description, also affirmed, in his usual manner, definite characters 
in the spiculation without taking into consideration the variability 
which is so marked a feature of the sponge. It is a puzzle to me 
how Haeckel arrived at the definition which he gave of Ascandra 
contorta, since the specimens named and identified by him which 
I have seen do not agree with his description, and belong, indeed, 
to other species—a fact which easily explains any errors of 
description on his part. It is even more mysterious that Haeckel 
should have considered his contorta identical with Bowerbank’s 
contorta, since, of Bowerbank’s specimens examined by me, eight 
in all, not one agrees with Haeckel’s diagnosis! These enigmas 
are not, however, of importance to the present enquiry. Taking 
Haeckel’s description as it stands, and allowing for a certain 
margin of inaccuracy, I have been able without difficulty to refer 
to Haeckel’s Ascandra contorta a sponge extremely abundant on 
the Mediterranean coasts of France, and occurring elsewhere 
also. As I have stated in a previous memoir, I consider that 
where previous writers leave us in doubt as to the characters of a 
species, Haeckel’s description fixes the application of the name. 
J will proceed now to describe the sponge which I regard as the true 
contorta, and then to consider the synonymy and application of 
the name. 
Ascandra contorta H. is a species which, for reasons stated 
elsewhere [4, &c.], I refer to the genus Clathrina Gray (1867). It 
has a closely reticulate mode of growth, equiangular triradiate 
systems, collar-cells with basal nucleus, and parenchymula larva ; 
all these being characters which make up my diagnosis of the 
genus Clathrina. 
