2/6 JOHANNA M. DIECKMANN. 



EXPLANATION OF FIGURES. 

 PLATE I. 



FIGS, i to 10. Diagrammatic cross-sections of the cloaca of a typical adult 

 Gyrinophihts female of 16.5 cm. The levels at which these were taken are indicated 

 on Fig. it, a semi-diagrammatic median sagittal section of an animal of the same 

 size. (Magnification, approximately X n.) 



FIG. i. Section passing through vent and entrance to dorsal diverticulum. 



FIG. 2. Through vent and diverticulum. 



FIG. 3. Ahead of vent, through diverticulum. 



FIG. 4. Ahead of vent and diverticulum; cuts through most caudal part of 

 gland region. Though most of the glands lie slightly more cephalad, their ducts 

 reach the surface at this level, opening upon, and between, the folds of the lateral 

 and ventral walls of the cloaca. Dorsally, the elevation divided into two folds 

 by the median dorsal slit, is shown. 



FIG. 5. Through caudal part of spermatheca, showing the two limbs of the 

 dorsal elevation in the dorsal wall of the cloaca; and, above, the two branches of 

 the common tube, with tubules streaming from them. 



FIG. 6. Through cephalic part of spermatheca; showing common tube opening 

 into mid-dorsal slit. 



FIG. 7. Cephalic to spermatheca; showing fusion of the two limbs into a 

 single broad dorsal elevation. 



FIG. 8. Cephalic to Fig. 7; the dorsal elevation breaking into three folds, 

 of which the median is slender and taller than the other two. 



FIG. 9. Through caudal end of bladder; in dorsal wall of cloaca, the three 

 folds seen in Fig. 8 ; the lateral folds are merging into the lateral wall of the cloaca. 



FIG. 10. Through the dorso- ventral expansion of the cloaca. Below the 

 cloaca communicates with the bladder. Into the dorsal expansion, farther cepha- 

 lad, open the ureters and oviducts. Parts of kidneys are shown above. 



FIG. ii. Semi-diagrammatic median sagittal section of cloaca of Gyrinophilus 

 female of 16.5 cm. The levels of Figs, i-io are indicated. 



