only in these cases!) it may be written so. Naturally there are transi- 
tions; in several cases one person will write this, another that, just 
as two persons in describing the shape of spieules will not always 
agree whether they are patento-ternate or expando-ternate , of course. 
In such cases it is perhaps practical to put the sign in parenthesis. 
So I have done this often when f. i. in subspinulate spieules the 
heads are very indistinet, or when spicules are not fusiforme but 
subfusiform. One will see often formulas as (tr) ac, tr. ac. (f), 
ac? (sp.), etc. 
The sign NB is added, when the shape is an extraordinary one. 
The anchorates of Chondrocladia and Cladorhiza f. i. have another 
shape than the common anchorates. 
The system of Mr. Gray contains innumerable things which are 
absolutely wrong and useles. I wish however to accept his 
distinetion of two great groups, viz. 1°. Porifera calcarea and 
2°. the other Sponges, which Gray!) unhappily calls Poriphora 
(to read Porifera) silicea. The diagnosis he gives, makes that 
there is no doubt possible about his meaning „Sponges, provided 
with a siliceous or horsy skeleton, or with a horny skeleton streng- 
thened with siliceous spieules”. I propose for this group, which 
is indeed composed of Sponges more closely allied with another 
than with the Calcareous Sponges, simply-the term: Porifera non- 
calcarea. 
A. PORIFERA CALCAREA. 
There were dredged only four small specimens of Calcareous 
Sponges. Now for a good determination it is indispensable to make 
some slices 'and to reserve a piece for boiling with kali causti- 
'eum in order to study the spicules. I have not been able to make 
slicees enough, for the specimens are small and seem to belong each 
to another species. For that reason I have still some doubt about 
the determination. 
1) Proceed. Zool. Soc. 1867 pag. 502. 
