62 DR J. STEPHENSON ON 
As to its anatomical features, the worm was 4 to 4 inch (8 to 12 mm.), in length, fili- 
form, white in colour, very sluggish. Prostomium short, rounded ; head-pore visible as 
a somewhat elongated slit, at the junction of prostomium and first seement; clitellum 
extending over most of xii. and half or more of xiii. ; segments thirty-eight to forty-five. 
Dorsal pores from vil. onwards, some little distance behind the septa ; with two cells in 
relation to each, granular and with large nuclei, one anterior and one posterior. 
The set# are absent in xu. ; form, numbers, and distribution as previously recorded. 
The larger (outer pair) setee are comparatively short in the first segments (047 mm.), 
and their leneth increases towards the clitellar region, near which it attains a first 
maximum (066 mm.); diminishing in the middle region of the body (‘048 mm.), the 
leneth again increases, and reaches a second maximum, higher than the first ((075 mm.), 
near the posterior end. Their thickness varies a little; it is often about a tenth of 
their length, or even more, 7.e. (0044 to 0057 mm. (cf. fig. 14, a). 
Fie. 14.—a, large sete of Fridericia bulbosa, 
b, a group of sete of the same, showing 
relation of smaller set to the larger. 
The smaller setze, included between the larger in the anterior part of the body, 
have their outer ends on a level, or almost so, with the ends of the large sete, but 
their hooked inner ends are at a more superficial level. In length they are about two- 
thirds the size of the larger, 7.e. 03 to ‘04 mm. (ef fig. 14, b). 
The peptonephridia enter the cesophagus in segment iv., and extend back to the 
level of the setee of v. They are not, in my specimens, branched or expanded at 
their ends. 
The dorsal vessel originates in segments xix., xx., or xxi. The blood is colourless. 
The calomic corpuscles are all of one kind, large, flat, oval discs, granular, nucleated, 
up to ‘022 mm. in diameter. The nephridia have the characters given in previous 
descriptions, the ante-septal portion being comparatively large, about one-third to one- 
fourth the length of the post-septal. The cerebral ganglion is twice as long as broad, 
with a rounded posterior end; it extends back a considerable distance into segment ii. ; 
its lateral margins converge somewhat towards the front. The ventral nerve-cord has 
copulatory glands (“ Bauchmarkdriisen ”) associated with it in segments xiii. and xiv, 
