357 
to our Knowledge of the Spongida. 
the cortex, Chondrilla phyllodes seems to have been placed 
among the Gumminida, and Spirastrella cunctatrix, on account 
of its crust, among Schmidt’s Corticatae (Spongien von Algier, 
P- 17). 
Now precisely the same species in point ot spiculation 
occur at the Mauritius and on the south coast of Australia, as 
I learn from specimens in the late Dr. Bowerbank’s collec¬ 
tion and that of the Liverpool Free Museum respectively. 
In all there is the usual condensed layer of flesh-spicules on 
the surface; and all present the fine crumb-of-bread-like con¬ 
sistence (areolated sarcode) observed in Ilalichondria suberea , 
Johnst.,= Suberites domuncula , Nardo. But while the former 
possess spinispirulate flesh-spicules like those of Spirastrella 
cunctatrix , represented by Schmidt (Spongien, 1. Suppl. Taf. 
iv. fig. 12, and Spong. von Algier, Taf. iii. fig. 8), that of the 
specimen in the Liverpool Museum, which has grown on the 
back of a little crab, is, together with the skeleton-spicule, a 
little shorter and stouter (PI. XXIX. fig. 12). Indeed there 
is much the same difference between the two as there is be¬ 
tween Schmidt’s illustrations of the flesh-spicule of Spirastrella 
cunctatrix and Chondrilla phyllodes respectively, all having 
the same pin-like skeleton-spicule. 
Hence it becomes questionable, with such varietal diffe¬ 
rences only in the spiculation, whether the difference in con¬ 
sistence may not be local, viz. gelatinous in Chondrilla phyl¬ 
lodes from the Antilles, and crumb-of-bread-like in the 
Suberite on the crab’s back from the Mauritius. 
There were five of these little crabs from the Mauritius sent 
for examination, each of which was about half an inch in 
diameter, and each overgrown by a different organism. Thus 
they bore respectively Ilalichondria incrustans , Isodictya , the 
white Suberite mentioned, Chondrilla nucula, Chondrosia, sp., 
and a calcareous white compound tunicated animal; so that I 
had ample means of contrasting the friable consistence of the 
Suberite with the gelatinous one of the Gumminida; while 
the spiculation of the former only differing from the other 
Suberites in the way above mentioned, led me to regard the 
whole as specimens of Schmidt’s Spirastrella cunctatrix , one 
of which, viz. that from Australia (Freemantle), now num¬ 
bered “ 708,” measures 6x4x2 inches in its greatest dimen¬ 
sions. Both this and those from the Mauritius, although dry, 
still present the remains of the violet-red colour which they 
had when fresh, together with some great variety in the length, 
size, and general form of the flesh-spicule ; while that on the 
crab’s back is white and the spiculation more robust. 
