1164 
We see thus that there are specimens of Hymeniacidon sanguinea 
which are only thin inerustations but that others tend to grow out. 
Indeed 1 examined several such specimens and they gradually lead 
to really more massive ones. All these specimens doubtless belong 
to the same species, which I, therefore, all determined as H. sanguinea. 
Some of them show an unmistakable likeness to certain specimens 
of Scumipt’s “Acanthella”, e.g. specimens 607, 749, 1154. Now it 
must be remembered that Scumipr (1862 p. 66), in describing his 
Suberites crambe and S. fruticosus, draws attention to their external 
resemblance to Acanthella. Of the former he wrote: “Diese Art 
wiirde man nach dem äusseren Habitus für eine Acanthella halten, 
indem die Oberflache des blättrig und lappig gefalteten Körpers mit 
stumpfen Dornen besetzt ist” and about S. fruticosus SCHMIDT says: 
“Auch die Gestalt dieser Art erinnert an Acanthella obtusa.” On the 
other hand Torserr taught us (1894 © p. XXXV and 1894 dp. 314) 
that in Banyuls Scumipt’s Suberites fruticosus *) often occurs in thin 
crusts. These red inerustations were already known to Torserr and 
described under the name of Siylinos brevicuspis (1892 « p. XX). 
So far for the external appearance. If we now examine the 
microscopic structure and the spicules we find the same variability 
as we found in the inerusting specimens. 
A specimen which comes very near 16 is 749. In both the 
skeleton is built up chiefly of styli of various dimensions, only in 
749 we find in addition some strongyla. It is, however, evident 
that these strongyla are modified styli. Torpsenr found in his Sé/ynos 
brevicuspis that the styli were characterised by the shortness of the 
pointed extremities. Topsent proceeds (1892 « p. XX): “leur pointe - 
(est) parfois reduite à un mucron ou meme tout a fait atrophiée”. 
This is exactly what often happens in my specimens. In some there 
are more, in others there are fewer strongyla, but a comparison of 
several specimens teaches us clearly that the presence or absence 
of strongyla is of no specifie value. We have seen already that this is 
likewise the case in the inerusting specimens with regard to acan- 
thostyli, chelae and sigmata. In the massive or pseudo-massive ones 
if is the same. The specimens 484 and 486 resemble each other 
most strikingly, but the relative number of acanthostyli and their 
grade of spination differ slightly. Moreover I found, after a long and 
careful examination, a few isochelae in 484. Again in another 
specimen (487) which nobody could externally distinguish from 
486, there are no acanthostyli, but a few more isochelae than 
in 484. Surely all these specimens are identical with specimen 16, 
') Topsent calls it Crambe fruticosus and afterwards Tetrunthella fructicosa. 
