SPONGES 21 
Another case of eccentric budding is ina sponge nine inches high, where 
a bud had originated some two inches from the base ; but upon making a long- 
itudinal section of this specimen, I found that the central tube of the large cyl- 
inder was abnormally narrow for two inches of its basal length, being only about 
a half inch wide, and the origin of the bud is just above this narrow portion. 
In a sponge having two cylinders, one seven and the other four inches 
high, two buds have appeared between the cylinders, one above the other, the 
highest being 2.50 from the base, and the other is directly beneath it : but both 
those buds adhere to the largest cylinder, and I find by measuring the depth 
of its tubes that the lower bud is really basal. Furthermore, the walls of the 
sponge are abnormally thickened, at the part where the buds appear, and as 
both the buds are of the same size, they probably originated about the same 
time if not simultaneously, and their appearance was probably induced by the 
abnormal thickness of the walls at this point. 
In another case in a group of three cylinders where the buds have ap- 
peared above the base, I find that the Verongia has been attacked by a para- 
sitical sponge of the genus Funiculea. Another specimen, also having three 
cylinders, which has been attacked by a parasitical sponge, belonging to the 
Spiculiginous group, has several escules formed, but they are very shallow, and 
are quite similar te those found in the branching species of the genus Verongia- 
In another sponge which was of an unknown length, of which I have a 
section about a feot long, in which two or three tubes have become twisted and 
distorted by the clinging of a parasitical sponge, buds and branches have ap- 
peared in several places, not at all near the base. 
Many species of sponges have the orifice of the excurrent tubes partly 
closed by a circular membrane which projects out like a collar from the margin. 
This membrane is quite prominent in the Tube Sponge. In this species 
the closing membrane at the termination of the central tube is somewhat vari- 
able in its position. Jt is usually quite near the extremity of the tube, not 
