Dr. J. E. Gray on the “Glass-Rope” Hyalonema. 289 
I described (t. 1, & t. 2. f. 1 & 2)—all the sponges having a flat 
base, by which they were evidently attached to some ‘marine 
body. 
Troteuate Brandt also figured (t. 1. f. 4&5) a specimen which 
has the basal part surrounded by a slender oblong mass of 
sponge ; but this sponge does not show any expanded base, and 
seems only like a parasitic sponge attached to the base of the 
coral, as sponges are often found on sea-weeds; and the figure 
shows a sponge of a much finer texture, so that it does not seem 
to be the same kind of sponge as that attached to my specimen 
or those described and figured by Professor Schultze. 
Observing that the polypes on all sides of the cylindrical coral 
were equally developed, I came to the conclusion that the coral 
must have grown in an erect position, so that the animals could 
all have equal access to the sea and an equal opportunity of pro- 
curing their food. 
Again, the specimens being sunk in a sponge that had a flat 
base by which it was attached to some marine body, I concluded 
that the natural habit of the animal was to develope itself in a 
sponge, so as to support itself in an erect position ; and this idea 
was strengthened by finding that the sponge near the part where 
the coral perforated it was of a more condensed and harder tex- 
ture than the other parts of it. I concluded that there was a 
kind of mutual understanding (such as we often find between 
animals that are parasitic on one another) between the sponge 
and the coral. 
It was for that reason that I formed for the genus the order 
before referred to, which I called Spongicole or Hyalophyta. 
(See Ann. & Mag. Nat. Hist. 1859, iv. p. 439.) 
It is true that the larger number of the specimens that are 
imported from Japan are without any appearance of a sponge 
at their more slender base; but I think it is very probable 
that the Japanese, who collect them as ornaments for sale, and 
who generally take off the larger part of the bark of the upper 
portion of the coral, may also carefully remove any sponge which 
they may think disfigures the specimen. 
This habit of living sunk in a sponge does not seem to be- 
long to all the species of the genus, and may not be univer- 
sal, or even general among the species found in Japan; and 
that may explain why the specimens imported are generally 
destitute of any appearance of ever having been immersed in a 
sponge. 
Professor Barboza du Bocage specially observes that the Por- 
tuguese species has never been found living in a sponge; his 
words are,— La cohabitation ou l’existence simultanée sur le 
méme axis de polypes et d’éponges, qu’on a remarquée sur quel- 
