150 BRODE. [Vor. XIV. 
prostonium is very much thickened and is thickly set with 
sensory cells. 
(d) Epzdermal Glands. 
In addition to the scattered gland cells mentioned above 
there are some other modifications of the epidermis which very 
probably are glandular in their nature. 
The clitellum covering segments V—VII during the time of 
sexual development has not been specially studied in this form, 
but the structure and function is in all probability much the 
same as has been described in other Oligochaetes. 
Near the posterior border of every segment beginning with 
segment VI there is a marked band of cells in the hypodermis 
(Pl. XIV, Fig. 10, g/d.) which when treated with ordinary 
reagents appear as empty cells surrounded by a substance 
taking a stain somewhat more deeply than other parts of the 
epidermis. | 
Another peculiar band (Pl. XIV, Fig. 10, @.gr.) appears in 
specimens stained with methylen blue. It is situated just 
posterior to the anterior girdle of sense organs and consists of 
very deep-staining dots regularly arranged on all segments 
back of the first five. Connecting the dots in the band there 
appears a narrow groove in the epidermis. 
I have not made a careful study of these structures, and my 
reason for mentioning them is on account of their metameric 
arrangement. 
(e) Muscles. 
There are two layers of muscles in the body wall, an outer 
circular and an inner longitudinal layer. The muscles are all 
of the so-called Nematoid type. 
The circular muscles (Pl. XIV, Fig. 18, ¢.mus.) are arranged 
in a single layer just beneath the epidermis. The nucleated 
plasma parts are gathered in the two lateral lines (Pl. XIV, 
Fig. 18, 2.7.) of the worm lying in the breaks between the dor- 
sal and ventral halves of the longitudinal muscles. This pecu- 
liar arrangement of nuclei was first made out by Hesse,! and I 
1R. Hesse, Beitrage zur Kenntnis des Baues der Enchytraeiden, Zezt. f. wiss. 
Zool., Ba. LVII, 1893, p. 6. 
