350 
BULLETIN OF THE UNITED STATES FISH COMMISSION, 
DESCRIPTION OF PLATES. 
Plate I. 
Diurella tigris Muller. 
1. Dorsal view, showing the ridge (x 350). 
2. Ventral view of trophi, a little from the left (x 665). 
3. Ventral or ventro-sinistral view ( X 350). 
4. Ventral or ventro-sinistral view of strongly retracted 
specimen ( x 350) . 
5. Optical section of body from rear ( x 350). 
6. Ventral view of foot and toes, with mucus reservoirs 
(to. r.) (x 600). 
Diurella tenuior Gosse. 
7. Small specimen, dorsal or dorgo-dextral view (X 350). 
8. Larger specimen, dorsal or dorso-dextral view (x 
.350). 
9. Ventral view of toes (X 600). 
10. Trophi, dorsal view (X 600). 
Diurella iveberi n. sp. 
11. Ventral view of toes under pressure ( x 665). 
12. Right side view (x 600). 
13. View of anterior edge of lorica, from the right (x 
350). 
14. Lorica, from left side (x 350). 
Plate II. 
Diurella insignis Herrick. 
15. Ventro-dextral view, head retracted (X 350). 
16. Dorsal view, retracted (x 350). 
17. Toes, pressed out, ventral view (x 350). 
18. Young specimen, ventro-dextral view (X 350). 
Diurella porcellus Gosse. 
19. Dorsal view (x 350). 
20. Lorica, from right side ( x 350) . 
21. Left side of extended specimen (x 350). 
22. Trophi, ventral view (of. trophi in fig. 21) (x 665). 
23. Foot and toes, dorsal view (the toes were bent be- 
neath body, as in fig. 21; animal viewed from ven- 
tral side) (x 665). 
Diurella sulcata . Jennings. 
24. Left side, foot extended (x 350). 
25. Right side, foot retracted (X 350). 
26. Trophi, dorsal view (x 665). 
Plate III. 
Diurella. stylata Eyferth. 
27. Right side (x 385). 
28. Dorsal view of retracted specimen ( x 385). 
29. Dorsal view of extended specimen ( x 385). 
30. Left side of retracted specimen ( x 385). 
31 Corona (X 600). 
Diurella brachyura Gosse. 
32. Right side (x 600). ev. for c. r.=cont,ractile vacuole. 
33. Left side of lorica, showing pro) ecting point on left 
side of anterior margin (x 600). 
34. Toes, dorsal view (X 665). 
Diurella cavia Gosse. 
35. Dorsal view (x 350). 
36. Right side, showing sac-like protrusion of lorica above 
and behind toes (x 350). 
Plate IV. 
The figures on this plate, except figs. 37 and 38, were 
drawn by Mr. F. R. Dixon-Nuttall, of Eccleston Park, 
near Prescot, England, who kindly placed them at the 
disposal of the author for the pi’esent paper. 
Diurella rousseleti Voigt. 
37. Side view of retracted specimen (x 600). 
38. Toes, ventral view ( x 665). 
39. Side view of retracted specimen. 
Diurella. dixon-nuttalli n. sp. 
40. Right side. 
41. Right side of another specimen. 
42. Trophi, dorsal view. 
43. Toes, dorsal view. 
44. Leftside. 
Plate V. 
Ra ttulus gracilis Tessin. 
45. Right side of much-extended specimen < from Prescot 
England) (x 350). 
46. Dorsal view (from Huron River, Michigan) (x 350). 
47. Dorsal view of lorica (from Prescot, England) (x 350). 
48. Dorsal view of anterior part of retracted specimen 
(X 350). 
49. Ventral view, trophi extended (x 350). 
Rattulus scipio Gosse. 
50. Ventro-dextral view of extended specimen (x 350). 
51. Dorso-dextral view of extended specimen, young 
(x 350). 
52. Dorsal view of retracted specimen ( x 350). 
Rattulus macerus Gosse. 
53. Right side of young specimen, retracted (x 285). 
•sp. = spur. 
54. Right side of adult specimen, extended ( x 285). sp.= 
spur. 
Plate VI. 
Rattulus multicrinis Kollieott. 
55. Dorsal view of lorica (x 350). 
56. Side view, with head and mastax extended ( x 350). 
57. Ventral view of extended specimen (x 350). 
58. Side view of anterior part of lorica when the head is 
strongly retracted (x 350.) 
