1907-8.] Oligochsets found on the Scottish Loch Survey. 
27 
LITERATURE. 
(1) JBenham, “Aquatic Oligochaets,” Q.J.M.S. -, xxxiii. 
(2) Beddard, Monograph of Oligochcets. 
(3) Bretscher, Revue Suisse de Zoolugie , 1889. 
(4) Claparede, Mem. Soc. Physiol. Geneve , xvi. 
(5) Grube, “Flora v. Eauna Schweitzerseen,” J. B. Schles. Ges., 1878, pp. 1 15— 
117; 1879, p. 228. 
(6) Yejdovsky, System v. Morphologie des Oligochcets , Prag, 1884. 
(7) Beddard, Monograph of Oligochcets. 
(8) Bourne, “On Naidiform Oligochaets,” Q.J.M.S., vol. xxxii., 1891. 
(9) Yejdovsky, Monograph des Oligochcets. 
Fig. 1. Section through the anterior testes and spermathecse. A + 6 comp. oc. 
Fig. 2. Section through the ducts of the spermathecse. A + 2 oc. 
Fig. 3. Section through aperture, vas deferens, and penis. 
Fig. 4. Section through posterior testes. 
Fig. 5. Section through oviduct. 
Fig. 6. Cocoon. 
Fig. 7. Section through the base of a ripening egg. 4 oc. + 2 mm. 
DESCRIPTION OF PLATES. 
Plate I . — Stylodrilus Gabretece. 
(Figs. 6 and 7 will be found on Plate IV., page 34.) 
Ch. chaeta. 
Chi. chloragogen cells. 
Sp. S. sperm sac. 
Sp. T. spermatheca. 
Fu. v. d. funnel of vas deferens. 
G. gut. 
M. muscle plates. 
0. oviduct. 
Ov. ovum. 
Pe. penis. 
Sp. sperm. 
Supra Int. supra-intestinal blood- 
vessel. 
Sub. Int. sub-intestinal. 
Sep. septum. 
Te. testis. 
V. D. vas deferens. 
Plate II. — Stylaria Lomondi. 
Fig. 1. Head end, stained specimens. A + 2 oc. 
Fig. 2. Transverse section through posterior segments. A + 2 oc. 
Fig. 3. Dorsal bundle. 6 comp. + 4 mm. 
Fig. 4. Yentral chaetae. 6 comp. + 2 mm. 
D.V. dorsal vessel. 
D.C. dorsal chaetae. 
Int. intestine. 
N.C. nerve cord. 
V.S. visceral sinus. 
V V. ventral vessel. 
(Issued separately December 24 , 1907 .) 
