Fig. 
Fig. 
Fig. 
ANATOMY AND HISTOLOGY OF PLEUROCHATA MOSELEYI. 509 
5.—Section through body wall cut transversely to circular coat: septa of fibrous tissue 
and muscular fibres between. x 120. 
6.—Section through clitellum. a, remains of hypoderm; below this gland cells; ¢, 
circular muscle coat; 7’, longitudinal muscle coat. x 60. 
7.—Section through clitellum, more highly magnified. x 200. 
8.—Fimbriated organ. x3. 
9.—Mesentery, showing relative positions of a, rosette-shaped body ; 8, fimbriated organ ; 
c, ventral blood-vessel. 
. 10.—Diagram of longitudinal muscle coat of Lwmbricus, cut transversely. 
g. 11.—Portion of clitellum, to show invasion of muscular fibres into glandular layer. x 540, 
g. 12,.—Transverse section through intestine in region of kidney-shaped glands; d, cells of 
peritoneal cavity. 
. 13,—Section through body wall in anterior region, cut rather obliquely; a, marks 
boundary between circular and longitudinal coats; 0, special muscular layer 
uniting setze of one segment. x 200. 
. 14.—Transverse section through fimbriated organ. 
. 15.—Transverse section through anterior end of young Plewrocheta, to show the com- 
partments in which the longitudinal muscles are arranged. x 200. 
. 16,—Oblique section through body wall, showing special muscles serving for the protrusion 
of the seta. x 120. 
. 17.—Unicellular glands, from clitellum. x 540. 
g. 18.—Polygonal epithelial cells, from surface of fimbriated organ. 
g. 19.—Section through kidney-shaped gland. «a, septum between two lobules. x 20. 
IP GATE Xexev Til. 
1.—Commissure connecting cerebral ganglia with ventral nerve chain. 
2,—Anterior part of nerve cord. ¢, cerebral ganglia; 0, commissure, enlarged in fig. 1. 
3.—Section through a ganglion of ventral chain. x 200. 
4,—Section through a ganglion of ventral chain. x 30. 
5,—Section through middle part of commissure uniting two ganglia. x60, 
. 6, 7. Embryos taken from cocoon, Natural size. 
8.—Gizzard cut open in middle, showing the chitinous lining, a. Natural size. 
9.—Section of a portion of one of the kidney-shaped glands. x 200. 
. 10.—Stout mesenteries in anterior part of body. Natural size. 
11.—Embryos from cocoon before being separated from each other. Natural size. 
ig. 12.—Cocoon. Natural size. 
g. 13.-—Transverse section through body wall of embryo on dorsal side. ¢, hypoderm; ¢, 
transverse muscular coat; ¢’, longitudinal coat. 
14.—Strip of the skin of young Plewrocheta, to show the setee and their special muscles. 
15.—Diagrammatic vertical section through Plewrocheta, to show arrangement of setz. 
16.—Strip of skin from dorsal part of embryo, from the same region as fig. 13. 
VOL, XXX. PART II. 4k 
