ILLUSTRATIONS. 
IX 
Plate 
No. Page. 
43. (Fig. 166) Bud of right fourth pereiopod in process of regeneration from young Lobster. (Fig. 167) Part of 
transverse section of oviduct of Lobster, with ovary nearly ripe. (Fig. 168) Part of transverse section 
of oviduct of Lobster, with external Eggs in early yolk segmentation. (Fig. 169) Longitudinal section 
of first, second, and third segments of right first, pereiopod of young Lobster in sixth stage. (Fig. 170) 
Internal surface of cuticle of second joint of first maxilla. (Fig. 171) Part of section of gastrolithic 
plate from female Lobster with hard shell. (Fig. 172) Section of left first pereiopod of Lobster 9 inches 
long, in process of regeneration. (Fig. 173) Section of bud of right first (crushing) cheliped of adult 
male Lobster. (Fig. 174) Part of longitudinal section of first Larva 252 
44. (Fig. 175) Eight fourth pereiopod of adult Lobster in process of regeneration, from below. (Fig. 176) Stump of right 
first pereiopod of adult Lobster iu course of regeneration, from below. (Fig. 177) Surface view of mem- 
brane between old and new shells of molting Lobster. (Fig. 178) Right second pereiopod of adult Male in 
process of regeneration, from below. (Fig. 179) Left second antenna of adult Lobster in process of regener- 
ation, from above. (Fig. 180) Antennae of the Isopod, Ligea oceanica, from above ; that of the left side in 
course of regeneration. (Fig. 181) Regenerating left antenna of the same, showing the new flagellum 
inclosed in the exoskeleton of the joint. (Fig. 182) Left first cheliped of adult Lobster in process of regen- 
eration, seen from the inner and anterior side. (Fig. 183) Profile view of masticatory stomach of Lobster, 
showing gastrolithic plate. (Fig. 184) Profile view of masticatory stomach of Male Lobster 7.5 inches 
long, nearly ready to molt 252 
45a. (Fig. 185) Molted shell of Lobster shown in Fig. 186 252 
456. (Fig. 186) The soft. Lobster, shortly after the shell shown in Fig. 185 was cast off 252 
46. (Fig. 187) Left, cheliped of Lobster, from below, showing budding and repetition of parts in propodus or sixth joint . 
(Fig. 188) Same as Fig. 187, seen from above 252 
47. (Fig. 189) Part of right, crushing-chela of Female Lobster, showing budding of dactyl. (Fig. 190) Propodus of left 
crushing-claw, from below. (Fig. 191) Left crushing-claw, seen from above; outgrowth from dactyl in 
horizontal plane. (Fig. 192) Left crushing-chela, from above; secondary dactyl bent downward slightly. 
(Fig. 193) Right cutting-chela, from below; fingers bent up; dactyls articulate at joint with propodus. 
(Fig. 194) Dactyl of left cutting-claw, seen from below. (Fig. 195) Chela of second and third pereiopod, 
from below, showing two supernumerary dactyls. (Fig. 196) Right dactyl of cutting-chela, seen from outer 
side 252 
48. (Fig. 197) Deformed right cutting-claw. (Fig. 198) Right, cutting-claw. (Fig. 199) Double monster of first 
Larva of Lobster. (Fig. 200) Double monster of first Larva of Lobster 252 
49. (Fig. 201) Gland-cell from tegumental gland of second maxilla. (Fig. 202) Gland-cell from same preparation as 
Fig. 201. (Fig. 203) Part of macerated tegumental gland from metastoma. (Fig. 204) Cell from macerated 
tegumental gland of first maxilla. (Fig. 205) Gland-cell from same preparation as F'ig. 204. (Fig. 206) 
Cell from macerated tegumental gland of abdominal appendage of Female before egg extrusion. (Fig. 
207) Same preparation as last, rolled under cover slip and seen from opposite side. (Fig. 208) Tegumental 
gland from metastoma of Female with ripe ovaries. (Fig. 209) Gland cell from tegumental gland of abdom 
inal appendage of Female. (Fig. 210) Tegumental gland of abdominal appendage of Female Lobster 
preparing to molt. (Fig. 211) Tegumental gland from abdominal appendage of Female after ovulation. 
(Fig. 212) Section of tegumental gland from abdominal, appendage of Female Lobster with mature ovaries. 
(Fig. 213) Gland-cells from same preparation as Figs. 204, 205. (Fig. 214) Macerated tegumental gland 
from metastoma of Female 252 
50. (Fig. 215) Egg before yolk has segmented. (Fig. 216) Surface view of Egg with 16 cells present near the surface. 
(Fig. 217) Same Egg as Fig. 216. (Fig. 218) Same Egg as in Figs. 216 and 217. (Fig. 219) Surface view of 
Egg showing yolk segments in active division. (Fig. 220) Reverse side of Egg shown in Fig. 219, corre- 
sponding to right side of Egg shown in Fig. 218, opposite the yolk hillocks. (Fig. 221) Surface view of 
segmenting Eggs. (Fig. 222) Surface view of segmenting Egg. (Fig. 223) Surface view of Egg. (Fig. 224) 
Surface view of Egg. (Fig. 225) Surface viewof Egg in advanced stageof yolk segmentation. (Fig. 226) 
Surface view of Egg in abnormal yolk segmentation 252 
51. (Fig. 227) Surface view of Egg in invagination stage. (Fig. 228) Surface view of abnormal embryo in egg- 
nauplius stage. (Fig. 229) Surface view of abnormal Embryo. (Fig. 230) Surface view of abnormal 
Embryo in egg-nauplius stage. (Fig. 231) Surface view of abnormal Embryo in egg-nauplius stage. 
(Fig. 232) Lateral view of Embryo, showing large white patch behind abdomen. (Fig. 233) Lateral view 
of Embryo about 5 weeks old, showing lateral fold of carapace covering the antenna;. (Fig. 234) Surface 
view of Embryo about 25 days old, showing the large optic lobes of cephalo thoracic appendages. (Fig. 
235) Lateral view of double monster in Egg-nauplius stage 252 
52. (Fig. 236) Part of transverse section of Egg. (Fig. 237) Part, of longitudinal section of Egg in egg-nauplius 
stage, showing degenerating cell. (Fig. 238) Part of transverse section of segmenting Egg, showing yolk 
cell. (Fig. 239) Part of section of segmenting Egg, showing yolk cell near center. (Fig. 240) Degenerat- 
ing cells from same preparation as shown in Fig. 237. (Fig. 241) Vesiculated masses of chromatin under- 
going degeneration in the yolk. (Fig. 242) Section of segmenting Egg. (Fig. 243) Section of Egg in late 
segmentation, showing formation of yolk cells and division of these in yolk. (Fig. 244) Surface view of 
Egg in late segmentation of yolk. (Fig. 245) Part of transverse section, showing multiple karyokinesis 
and formation of nests of nuclei. (Fig. 246) Part of transverse section through Embryo in invagination 
stage. (Fig. 247) Partof section of Egg to show nest of nuclei at surface. (Fig. 248) From section through 
Embryo in invagination stage. (Fig. 249) Fertilized Egg nucleus 252 
