Fic. 19. Astacus fluviatilis. 
” 
20. 
21, 
22. 
23. 
24, 
25. 
26. 
27, 
28. 
29. 
30. 
31. 
32. 
33. 
34, 
35. 
36. 
37. 
38. 
39. 
40. 
41, 
42. 
43, 
44, 
” 
it) 
LIST OF WOODCUTS. 
PAGE 
MUSCULAR TISSUE ‘ : ay an 9 
MUSCLES OF CHELA . 3 ‘ - 93 
ARTICULATION OF ABDOMINAL 860- 
MITES , 5 F 5 « » 97 
MUSCULAR SYSTEM . ‘ : . 100 
NERVE FIBRES. F ‘ - . 102 
NERVE GANGLIA ‘ ‘ . 103 
NERVOUS SYSTEM 104 
OLFACTORY AND AUDITORY oRGANS 114 
AUDITORY SAC. , : p . 17 
STRUCTURE OF EYE. a ta SELQ: 
DIAGRAM OF EYE. ji ‘3 . 128 
FEMALE REPRODUCTIVE ORGANS . 129 
MALE REPRODUCTIVE ORGANS . . 130 
STRUCTURE OF OVARY. 3 - . 131 
STRUCTURE OF TESTIS. ‘ - 182 
SPERMATOZOA : 3 ei » . 184 
THE LAST THORACIC STERNUM IN THE 
MALE AND FEMALE . 136 
TRANSVERSE SECTION OF ABDOMEN 142 
ABDOMINAL APPENDAGES . . 144 
CONNECTION BETWEEN THORAX AND 
ABDOMEN . ‘ : ‘ - 151 
CEPHALOTHORACIC STERNA AND EN- 
DOPHRAGMAL SYSTEM. ~ . 158 
OPHTHALMIC AND ANTENNULARY; 80- 
MITES . ‘ F ° - 156 
THE ROSTRUM. 3 ‘ » . 187 
A SEGMENT OF THE ENDOPHRAGMAL 
SYSTEM 3 : A , . 159 
LONGITUDINAL SECTION OF CEPHALO- 
THORAX . 3 . » . 162 
THE THIRD MAXILLIPBDE. 7 - 164 
