ove WILLIAM BLAXLAND BENHAM. 
times that of the epidermis; both muscular layers are well 
supplied with blood-vessels, which, however, do not penetrate 
the epidermis. 
Embedded in this layer are, here and there, more deeply- 
stained masses of cells, with well-marked nucleus in each 
(mlr. gl.) ; from these masses a duct may be traced towards the 
surface, but when it reaches the epidermis this duct has become 
very fine, so that, though doubtless it passes between the cells, it 
is very difficult tofollow. I regard these as multicellular glands, 
which open to the surface. 
In the region of the body between somites vi and 1x, the 
longitudinal muscular layer is enormously thick—that is, in the 
region of the strong septa—giving a very much greater rigidity 
and strength to the animal here than elsewhere. 
Beneath the longitudinal layer is another layer of fibrous 
connective tissue, thicker than the layer outside the longitudinal 
muscles, but similar to it, and continuous with it by the inter- 
mediation of the tissue around the muscle-strands. 
The parietal portion of the celomic epithelium (c@.ep. pa.) 
consists, as in Lumbricus, of flat cells whose nuclei are evident 
in sections. 
The Clitellum.—In the clitellum of Lumbricus we have 
the three following chief constituents Claparéde (11), and 
Mojsisovies (50) :— 
1. Ordinary columnar cells, but usually shorter than in 
the other regions of the body. 
2. Narrow, elongated cells, with globular granules similar 
to those found in the goblet cells of other parts of the 
epidermis; but these cells are much longer than the 
columnar cells, being nearly three times their length. 
3. Very long cells, swollen at their inner end, and con- 
taining densely packed minute granules; these are 
the club-shaped cells. They are five or six times 
the length of the columnar cells. 
These all have branched bases, and in the two last varieties 
the nucleus is found near the base of the cell. 
In Microcheta (Pl. XVI dis, fig. 41) we have a fourth 
