NOTES ON ACANTHODRILOID EARTHWORMS. 305 
feebly stained, and the contents of the cell remain unstained 
in borax carmine. 
The epithelium of the appendix (figs. 31 and 32 c) consists 
of tall columnar cells, not quite so high as those of the sac. 
The outer free end of each cell is flat, and the inner end of all 
the cells in my sections is bent at a slight angle to the body of 
the cells, and at this point lies the nucleus. This is smaller 
than that in the epithelium of the sac, and stains much more 
deeply: it is surrounded by a deepy staining almost homoge- 
neous protoplasm. The rest of the cell is occupied by similar 
granules to those found in the epithelial cells of the sac. 
The appendix is filled with spermatozoa, which are to some 
extent regularly arranged, with the heads towards the walls, 
and the tails directed centrally. The heads appear embedded 
in or attached to the epithelium (figs. 31, 32, d). The cells 
in these regions are much shorter, less than half the length of 
those just described; and have no definite outer surface: 
otherwise they resemble the above-mentioned cells. Inter- 
mediate conditions between ¢ and d can be seen in the sections. 
It is probable that the cells of the appendix do not simply 
discharge their product, but disintegrate, leaving only the 
nucleus and homogeneous protoplasm behind, which will come 
into renewed activity, and give rise to more secretion during 
the next breeding season. 
The spermatozoa, as seen in the section, are arranged as if 
they formed a sperm-rope, but the heads and tails are reversed 
when compared with sperm-rope of Tubificide, &c., which 
may perhaps be due to the fact that there would be no oppor- 
tunity for the use of the tails for locomotion of the sperm-rope 
in earthworms. 
We are totally ignorant of the purpose of this sperm-rope 
in earthworms, and it is a matter of some uncertainty as to 
where they are formed in Lumbricus, &c.; but it seems, 
from the above observations and others made by Beddard that, 
in those genera which have “ an appendix ”’ to the spermatheca, 
the sperm-ropes or spermatophores are formed in that portion 
of the organ. 
